https://github.com/ganeshrvel/pub-rules
Powerful and feature-rich validation library for both Dart and Flutter.
https://github.com/ganeshrvel/pub-rules
dart flutter mobx rules validation validation-library
Last synced: 2 months ago
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Powerful and feature-rich validation library for both Dart and Flutter.
- Host: GitHub
- URL: https://github.com/ganeshrvel/pub-rules
- Owner: ganeshrvel
- License: mit
- Created: 2020-05-08T16:20:50.000Z (over 5 years ago)
- Default Branch: master
- Last Pushed: 2021-04-18T15:09:14.000Z (over 4 years ago)
- Last Synced: 2025-04-03T17:39:45.367Z (8 months ago)
- Topics: dart, flutter, mobx, rules, validation, validation-library
- Language: Dart
- Homepage: https://pub.dev/packages/rules
- Size: 107 KB
- Stars: 25
- Watchers: 2
- Forks: 3
- Open Issues: 2
-
Metadata Files:
- Readme: README.md
- Changelog: CHANGELOG.md
- License: LICENSE
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- my-awesome-list - pub-rules - rich validation library for both Dart and Flutter. | ganeshrvel | 25 | (Dart)
README
### Introduction
##### Rules - Powerful and feature-rich validation library for both Dart and Flutter.
**Rules** is a simple yet powerful and feature-rich validation library for both dart and flutter.
#### Features
- Highly flexible
- Easy to understand
- Less boilerplate code
- Custom error handling
- Override individual errors
- Flutter friendly
- State management libraries friendly ([Mobx example included](https://github.com/ganeshrvel/pub-rules#flutter-mobx "Mobx example included"))
### Installation
Go to https://pub.dev/packages/rules#-installing-tab- for the latest version of **rules**
*To activate pre-commit hooks*
```shell
$ git config core.hooksPath .githooks/
$ chmod +x .githooks/pre-commit
$ chmod +x .githooks/pre-push
```
### Concept
The Rules library has three parts
- Rule: Basic rule
- GroupRule: Group together and validate the basic rules
- CombinedRule: Validate multiple basic rules and group rules together
### Usage
**Import the library**
```dart
import 'package:rules/rules.dart';
```
#### 1. Rule (Basic Rule)
This is the basic building block, everything starts here.
**Basic example**
```dart
void main() {
const textFieldValue = 'abc@xyz.com';
final rule = Rule(
textFieldValue, // value; string and null are accepted
name: 'Text field', // placeholder value which will be used while displaying errors
);
print(rule.error);
// output: null
print(rule.hasError);
// output: false
}
```
**Example 1**
```dart
void main() {
const textFieldValue = ''; // or const textFieldValue = null;
final rule = Rule(
textFieldValue,
name: 'Text field',
isRequired: true,
);
print(rule.error);
// output: 'Text field is required'
print(rule.hasError);
// output: true
if (rule.hasError) {
// some action on error
} else {
// Some action on success
}
}
```
**Example 2**
```dart
void main() {
const textFieldValue = 'abc@xyz';
final rule = Rule(
textFieldValue,
name: 'Text field',
isRequired: true,
isEmail: true,
);
print(rule.error);
// output: 'Text field is not a valid email address'
print(rule.hasError);
// output: true
if (rule.hasError) {
// some action on error
} else {
// Some action on success
}
}
```
**Available rules**
```dart
String name; // mandatory
bool isRequired;
bool isEmail;
bool isUrl;
bool isPhone;
bool isIp;
bool isNumeric;
bool isNumericDecimal;
bool isAlphaSpace;
bool isAlphaNumeric;
bool isAlphaNumericSpace;
RegExp regex;
int length;
int minLength;
int maxLength;
double greaterThan;
double greaterThanEqualTo;
double lessThan;
double lessThanEqualTo;
double equalTo;
double notEqualTo;
List equalToInList;
List notEqualToInList;
String shouldMatch;
String shouldNotMatch;
bool shouldPass(String value);
List inList;
List notInList;
```
**Available configurations**
```dart
String customErrorText;
Map customErrors;
RuleOptions options;
```
###### isRequired: `bool`
```dart
void main() {
const textFieldValue = '123';
final rule = Rule(
textFieldValue,
name: 'Text field',
isRequired: true, // throws an error for value = null or an empty string
);
if (rule.hasError) {
// some action on error
} else {
// Some action on success
}
}
```
- IMPORTANT: If the value is empty or null and 'isRequired' is false or not set then no errors will be thrown for the subsequent constraints.
```dart
void main() {
const textFieldValue = ''; // or null
final rule = Rule(
textFieldValue,
name: 'Text field',
isRequired: false,
isEmail: true,
);
print(rule.hasError);
// output: false
}
```
###### isEmail: `bool`
```dart
void main() {
const textFieldValue = 'abc@xyz.com';
final rule = Rule(
textFieldValue,
name: 'Text field',
isEmail: true,
);
if (rule.hasError) {
// some action on error
} else {
// Some action on success
}
}
```
###### isUrl: `bool`
```dart
void main() {
const textFieldValue = 'http://www.google.com';
final rule = Rule(
textFieldValue,
name: 'Text field',
isUrl: true,
);
if (rule.hasError) {
// some action on error
} else {
// Some action on success
}
}
```
###### isPhone: `bool`
- It recognizes the phone numbers starting with **+** or **0**, no length limitations and handles `#, x, ext, extension` extension conventions.
```dart
void main() {
const textFieldValue = '+1-9090909090';
final rule = Rule(
textFieldValue,
name: 'Text field',
isPhone: true,
);
if (rule.hasError) {
// some action on error
} else {
// Some action on success
}
}
```
###### isIp: `bool`
- It accepts both IPv4 and IPv6 addresses.
```dart
void main() {
const textFieldValue = '1.1.1.1';
final rule = Rule(
textFieldValue,
name: 'Text field',
isIp: true,
);
if (rule.hasError) {
// some action on error
} else {
// Some action on success
}
}
```
###### isNumeric: `bool`
- It accepts both 0, positive and negative integers. Decimals are not allowed.
```dart
void main() {
const textFieldValue = '1'; // '-1', '0'
final rule = Rule(
textFieldValue,
name: 'Text field',
isNumeric: true,
);
if (rule.hasError) {
// some action on error
} else {
// Some action on success
}
}
```
###### isNumericDecimal: `bool`
- It accepts 0, postive and negative integers and decimals numbers.
```dart
void main() {
const textFieldValue = '10.01'; // '-10.01' or '0.001'
final rule = Rule(
textFieldValue,
name: 'Text field',
isNumericDecimal: true,
);
if (rule.hasError) {
// some action on error
} else {
// Some action on success
}
}
```
###### isAlphaSpace: `bool`
- It accepts multiple spaces and alphabets (both upper and lower case).
```dart
void main() {
const textFieldValue = 'Jane Doe';
final rule = Rule(
textFieldValue,
name: 'Text field',
isAlphaSpace: true,
);
if (rule.hasError) {
// some action on error
} else {
// Some action on success
}
}
```
###### isAlphaNumeric: `bool`
- It accepts alphabets (both upper and lower case) and numbers.
```dart
void main() {
const textFieldValue = 'username123';
final rule = Rule(
textFieldValue,
name: 'Text field',
isAlphaNumeric: true,
);
if (rule.hasError) {
// some action on error
} else {
// Some action on success
}
}
```
###### isAlphaNumericSpace: `bool`
- It accepts multiple spaces, alphabets (both upper and lower case) and numbers.
```dart
void main() {
const textFieldValue = 'Bread 20';
final rule = Rule(
textFieldValue,
name: 'Text field',
isAlphaNumericSpace: true,
);
if (rule.hasError) {
// some action on error
} else {
// Some action on success
}
}
```
###### regex: `RegExp`
- It accepts a custom regular expression string.
```dart
void main() {
const textFieldValue = 'abc123';
final rule = Rule(
textFieldValue,
name: 'Text field',
regex: RegExp(
r'^[a-zA-Z0-9\s]+$',
caseSensitive: false,
),
);
if (rule.hasError) {
// some action on error
} else {
// Some action on success
}
}
```
###### length: `int`
- Defines the length of the input string.
```dart
void main() {
const textFieldValue = '9090909090';
final rule = Rule(
textFieldValue,
name: 'Phone Number',
length: 10,
);
if (rule.hasError) {
// some action on error
} else {
// Some action on success
}
}
```
###### minLength: `int`
- Defines the minimum length of the input string.
```dart
void main() {
const textFieldValue = 'abcd12345';
final rule = Rule(
textFieldValue,
name: 'Password',
minLength: 6,
);
if (rule.hasError) {
// some action on error
} else {
// Some action on success
}
}
```
###### maxLength: `int`
- Defines the maximum length of the input string.
```dart
void main() {
const textFieldValue = 'username12';
final rule = Rule(
textFieldValue,
name: 'Username',
minLength: 10,
);
if (rule.hasError) {
// some action on error
} else {
// Some action on success
}
}
```
###### greaterThan: `double`
- Checks if the input value is greater than the 'greaterThan' value.
- if 'isNumeric' is not set then the 'isNumericDecimal' constraint will be applied automatically.
```dart
void main() {
const textFieldValue = '10';
final rule = Rule(
textFieldValue,
name: 'Text field',
greaterThan: 0,
isNumeric: true, // optional
);
if (rule.hasError) {
// some action on error
} else {
// Some action on success
}
}
```
###### greaterThanEqualTo: `double`
- Checks if the input value is greater than or equal to the 'greaterThanEqualTo' value.
- if 'isNumeric' is not set then 'isNumericDecimal' constraint will be applied automatically.
```dart
void main() {
const textFieldValue = '5.1';
final rule = Rule(
textFieldValue,
name: 'Text field',
greaterThanEqualTo: 5.0,
);
if (rule.hasError) {
// some action on error
} else {
// Some action on success
}
}
```
###### lessThan: `double`
- Checks if the input value is greater than or equal to the 'lessThan' value.
- if 'isNumeric' is not set then 'isNumericDecimal' constraint will be applied automatically.
```dart
void main() {
const textFieldValue = '1';
final rule = Rule(
textFieldValue,
name: 'Text field',
lessThan: 2.0,
isNumericDecimal: true, // optional
);
if (rule.hasError) {
// some action on error
} else {
// Some action on success
}
}
```
###### lessThanEqualTo: `double`
- Checks if the input value is greater than or equal to the 'lessThanEqualTo' value.
- if 'isNumeric' is not set then 'isNumericDecimal' constraint will be applied automatically.
```dart
void main() {
const textFieldValue = '2.0';
final rule = Rule(
textFieldValue,
name: 'Text field',
lessThanEqualTo: 2.0,
);
if (rule.hasError) {
// some action on error
} else {
// Some action on success
}
}
```
###### equalTo: `double`
- Checks if the input value is equal to the 'equalTo' value.
- if 'isNumeric' is not set then 'isNumericDecimal' constraint will be applied automatically.
```dart
void main() {
const textFieldValue = '2.0';
final rule = Rule(
textFieldValue,
name: 'Text field',
equalTo: 2.0,
);
if (rule.hasError) {
// some action on error
} else {
// Some action on success
}
}
```
###### notEqualTo: `double`
- Checks if the input value is equal to the 'notEqualTo' value.
- It will throw an error if the values match.
- if 'isNumeric' is not set then 'isNumericDecimal' constraint will be applied automatically.
```dart
void main() {
const textFieldValue = '2.0';
final rule = Rule(
textFieldValue,
name: 'Text field',
notEqualTo: 2.0,
);
if (rule.hasError) {
// some action on error
} else {
// Some action on success
}
}
```
###### equalToInList: `List`
- Checks if the input value matches with any of the 'equalToInList' values.
- Note: This is a float comparison. 10.00 == 10 will be true.
```dart
void main() {
const textFieldValue = '10';
final rule = Rule(
textFieldValue,
name: 'Text field',
equalToInList: [0, 10],
);
if (rule.hasError) {
// some action on error
} else {
// Some action on success
}
}
```
###### notEqualToInList: `List`
- Checks if the input value matches with any of the 'notEqualToInList' values.
- It will throw an error if there is a value match.
- Note: This is a float comparison. 10.00 == 10 will be true.
```dart
void main() {
const textFieldValue = '10';
final rule = Rule(
textFieldValue,
name: 'Text field',
notEqualToInList: [0, 10],
);
if (rule.hasError) {
// some action on error
} else {
// Some action on success
}
}
```
###### shouldMatch: `String`
- Checks if the input value matches with the 'shouldMatch' value.
- Note: This is a string comparison.
```dart
void main() {
const textFieldValue = 'abc';
final rule = Rule(
textFieldValue,
name: 'Text field',
shouldMatch: 'abc',
);
if (rule.hasError) {
// some action on error
} else {
// Some action on success
}
}
```
###### shouldNotMatch: `String`
- Checks if the input value matches with the 'shouldNotMatch' value.
- It will throw an error if the values match.
- Note: This is a string comparison.
```dart
void main() {
const textFieldValue = 'abc';
final rule = Rule(
textFieldValue,
name: 'Text field',
shouldNotMatch: 'xyz',
);
if (rule.hasError) {
// some action on error
} else {
// Some action on success
}
}
```
###### shouldPass: `bool Function(String value)`
- Checks if the input value passes the given function check
- It will throw an error if the function returns false
```dart
void main() {
const textFieldValue = 'abc';
final rule = Rule(
textFieldValue,
name: 'Text field',
shouldPass: (value) => value.contains('a') && value.contains('b')
);
if (rule.hasError) {
// some action on error
} else {
// Some action on success
}
}
```
###### inList: `List`
- Checks if the input value matches with any of the 'inList' values.
- Note: This is a string comparison.
```dart
void main() {
const textFieldValue = 'abc';
final rule = Rule(
textFieldValue,
name: 'Text field',
inList: ['abc', 'xyz'],
);
if (rule.hasError) {
// some action on error
} else {
// Some action on success
}
}
```
###### notInList: `List`
- Checks if the input value matches with any of the 'notInList' values.
- It will throw an error if there is a value match.
- Note: This is a string comparison.
```dart
void main() {
const textFieldValue = 'abc';
final rule = Rule(
textFieldValue,
name: 'Text field',
notInList: ['abc', 'xyz'],
);
if (rule.hasError) {
// some action on error
} else {
// Some action on success
}
}
```
**Custom Error**
###### Default errors
```
'isRequired': '{name} is required'
'isEmail': '{name} is not a valid email address'
'isPhone': '{name} is not a valid phone number'
'isUrl': '{name} is not a valid URL'
'isIp': '{name} is not a valid IP address'
'isNumeric': '{name} is not a valid number'
'isNumericDecimal': '{name} is not a valid decimal number'
'isAlphaSpace': 'Only alphabets and spaces are allowed in {name}'
'isAlphaNumeric': 'Only alphabets and numbers are allowed in {name}'
'isAlphaNumericSpace': 'Only alphabets, numbers and spaces are allowed in {name}'
'regex': '{name} should match the pattern: {regex.pattern}'
'length': '{name} should be $length characters long'
'minLength': '{name} should contain at least $minLength characters'
'maxLength': '{name} should not exceed more than $maxLength characters'
'greaterThan': '{name} should be greater than $greaterThan'
'greaterThanEqualTo': '{name} should be greater than or equal to $greaterThanEqualTo'
'lessThan': '{name} should be less than $lessThan'
'lessThanEqualTo': '{name} should be less than or equal to $lessThanEqualTo'
'equalTo': '{name} should be equal to $equalTo'
'notEqualTo': '{name} should not be equal to $notEqualTo'
'equalToInList': '{name} should be equal to any of these values $equalToInList'
'notEqualToInList': '{name} should not be equal to any of these values $notEqualToInList'
'shouldMatch': '{name} should be same as $shouldMatch'
'shouldNotMatch': '{name} should not same as $shouldNotMatch'
'shouldPass': '{name} is invalid'
'inList': '{name} should be any of these values $inList'
'notInList': '{name} should not be any of these values $notInList'
```
###### Override the default errors
- To override the error text of a particular option, set 'customErrors' as `{'optionName': ''`}.
- The 'optionName' key should match with one of the 'Available rules' for overriding the error text.
- Use {value} and {name} template variables in the 'customErrors' to display the input name and value respectively.
- To override all default error texts set 'customErrorText'.
- Note: 'customErrorText' will only override the default errors. 'customErrors' will be given the highest priority.
```dart
void main() {
const textFieldValue = ''; // or textFieldValue = 'xyz';
final rule = Rule(
textFieldValue,
name: 'Text field',
isRequired: true,
isEmail: true,
customErrors: {
'isRequired': 'Input is invalid.',
'isEmail': '{value} is an invalid value. Try another {name}.',
},
);
// when textFieldValue = '';
print(rule.error);
// output: Input is invalid.
// when textFieldValue = 'xyz';
print(rule.error);
// output: xyz is an invalid value. Try another Text field.
}
```
```dart
void main() {
const textFieldValue = '123';
final rule = Rule(
textFieldValue,
name: 'Text field',
isRequired: true,
isEmail: true,
customErrorText: 'Invalid email address',
);
print(rule.error);
// output: Invalid email address
}
```
**Extension**
- Extend and override the constraints of a rule using 'copyWith' method
```dart
void main() {
const textFieldValue = 'abc';
final rule1 = Rule(
textFieldValue,
name: 'Text field 1',
isAlpha: true,
customErrorText: 'Only alphabets allowed',
);
final rule2 = rule1.copyWith(
name: 'Text field 2',
isEmail: true,
customErrorText: 'Invalid email address',
);
print(rule1.error);
// output: null
print(rule2.error);
// output: Invalid email address
}
```
- The child rule will default to the constraint values of the parent unless they are set explicitly in the child.
```dart
void main() {
const textFieldValue = '';
// parent rule
final rule1 = Rule(
textFieldValue,
name: 'Text field',
isRequired: true,
customErrorText: 'Invalid input',
);
// child rule
final rule2 = rule1.copyWith(
isRequired: false,
);
print(rule1.error);
// output: Invalid input
print(rule2.error);
// output: null
}
```
#### 2. GroupRule
Group together and validate the basic rules
**Basic example**
```dart
void main() {
const textFieldValue = 'abc@xyz.com';
final rule = Rule(
textFieldValue,
name: 'Text field',
);
final groupRule = GroupRule(
[rule], // value; List of Rule
name: 'Group name', // placeholder value which will be used while displaying errors
);
print(groupRule.error);
// output: null
print(groupRule.hasError);
// output: false
if (groupRule.hasError) {
// some action on error
} else {
// Some action on success
}
}
```
**Example 1**
```dart
void main() {
const textFieldValue1 = ''; // or const textFieldValue = null;
const textFieldValue2 = '';
final rule1 = Rule(
textFieldValue1,
name: 'Text field 1',
isRequired: true,
);
final rule2 = Rule(
textFieldValue2,
name: 'Text field 2',
isEmail: true,
);
final groupRule = GroupRule(
[rule1, rule2], // value; List of Rule
name: 'Group name', // placeholder value which will be used while displaying errors
);
print(groupRule.error);
// output: 'Text field 1 is required'
print(groupRule.hasError);
// output: true
}
```
**Available rules**
```dart
String name; // mandatory
bool requiredAll;
int requiredAtleast;
int maxAllowed;
```
**Available configurations**
```dart
String customErrorText;
Map customErrors;
```
###### requiredAll: `bool`
- Checks if all basic rules have a value.
```dart
void main() {
const textFieldValue1 = 'abc';
const textFieldValue2 = '';
final rule1 = Rule(
textFieldValue1,
name: 'Text field',
isRequired: true,
); // Validation OK
final rule2 = Rule(
textFieldValue2,
name: 'Text field',
); // Validation OK
final groupRule = GroupRule(
[rule1, rule2],
name: 'Group name',
requiredAll: true,
);
print(groupRule.error);
// output: All fields are mandatory in Group name
}
```
- IMPORTANT: If any of the basic rules have validation errors then GroupRule will throw those errors first.
- The group validation wouldn't happen until all basic rules pass the validation.
```dart
void main() {
const textFieldValue1 = 'abc'; // or const textFieldValue = null;
const textFieldValue2 = 'xyz@abc';
final rule1 = Rule(
textFieldValue1,
name: 'Text field 1',
isRequired: true,
); // Validation OK
final rule2 = Rule(
textFieldValue2,
name: 'Text field 2',
isEmail: true,
); // Validation FAILED
final groupRule = GroupRule([rule1, rule2], name: 'Group name');
print(groupRule.error);
// output: 'Text field 2 is not a valid email address'
print(groupRule.hasError);
// output: true
if (groupRule.hasError) {
// some action on error
} else {
// Some action on success
}
}
```
- IMPORTANT: If the input basic rules list is an empty array or null and 'isRequiredAll' is false or not set then no errors will be thrown for the subsequent constraints.
```dart
void main() {
final groupRule = GroupRule([], name: 'Group name');
print(groupRule.hasError);
// output: false
}
```
###### requiredAtleast: `int`
- Defines the minimum number of basic rules that should have a value.
- The number of basic rules in a GroupRule should be greater than the 'requiredAtleast' value else it will throw an exception.
- If the 'requiredAtleast' is 0 then it will pass the validation.
```dart
void main() {
const textFieldValue1 = 'abc';
const textFieldValue2 = '';
final rule1 = Rule(
textFieldValue1,
name: 'Text field',
); // Validation OK
final rule2 = Rule(
textFieldValue2,
name: 'Text field',
); // Validation OK
final groupRule = GroupRule(
[rule1, rule2],
name: 'Group name',
requiredAtleast: 2,
);
print(groupRule.error);
// output: At least 2 fields are required in Group name
}
```
```dart
void main() {
const textFieldValue1 = 'abc';
const textFieldValue2 = 'xyz';
final rule1 = Rule(
textFieldValue1,
name: 'Text field',
); // Validation OK
final rule2 = Rule(
textFieldValue2,
name: 'Text field',
); // Validation OK
final groupRule = GroupRule(
[rule1, rule2],
name: 'Group name',
requiredAtleast: 2,
);
print(groupRule.error);
// output: null
print(groupRule.hasError);
// output: false
}
```
###### maxAllowed: `int`
- The maximum number of basic rules that are allowed to have a value.
```dart
void main() {
const textFieldValue1 = 'abc';
const textFieldValue2 = 'xyz';
final rule1 = Rule(
textFieldValue1,
name: 'Text field',
); // Validation OK
final rule2 = Rule(
textFieldValue2,
name: 'Text field',
); // Validation OK
final groupRule = GroupRule(
[rule1, rule2],
name: 'Group name',
maxAllowed: 1,
);
print(groupRule.error);
// output: A maximum of 1 field is allowed in Group name
}
```
```dart
void main() {
const textFieldValue1 = 'abc';
const textFieldValue2 = '';
final rule1 = Rule(
textFieldValue1,
name: 'Text field',
); // Validation OK
final rule2 = Rule(
textFieldValue2,
name: 'Text field',
); // Validation OK
final groupRule = GroupRule(
[rule1, rule2],
name: 'Group name',
maxAllowed: 1,
);
print(groupRule.error);
// output: null
print(groupRule.hasError);
// output: false
}
```
**Custom Error**
###### Default errors
- Plurality for 'requiredAtleast' and 'maxAllowed' error texts will be automatically detected.
```
'requiredAll': 'All fields are mandatory in {name}'
'requiredAtleast': 'At least $requiredAtleast field(s) is/are required in {name}'
'maxAllowed': 'A maximum of $maxAllowed field(s) is/are allowed in {name}'
```
###### Override the default errors
- To override the error text of a particular option, set 'customErrors' as `{'optionName': ''`}.
- The 'optionName' key should match with one of the 'Available rules' for overriding the error text.
- Use {value} and {name} template variables in the 'customErrors' to display the input name and value respectively.
- To override all default error texts set 'customErrorText'.
- Note: 'customErrorText' will only override the default errors. 'customErrors' will be given the highest priority.
```dart
void main() {
const textFieldValue1 = 'abc';
const textFieldValue2 = '';
final rule1 = Rule(
textFieldValue1,
name: 'Text field',
isRequired: true,
); // Validation OK
final rule2 = Rule(
textFieldValue2,
name: 'Text field',
); // Validation OK
final groupRule = GroupRule(
[rule1, rule2],
name: 'Group name',
requiredAll: true,
customErrors: {
'requiredAll': 'Input is invalid.',
},
);
print(groupRule.error);
// output: Input is invalid.
}
```
```dart
void main() {
const textFieldValue1 = 'abc';
const textFieldValue2 = '';
final rule1 = Rule(
textFieldValue1,
name: 'Text field',
isRequired: true,
); // Validation OK
final rule2 = Rule(
textFieldValue2,
name: 'Text field',
); // Validation OK
final groupRule = GroupRule(
[rule1, rule2],
name: 'Group name',
requiredAll: true,
customErrorText: 'Invalid input.',
);
print(groupRule.error);
// output: Invalid input.
}
```
**Options**
##### Available options
```dart
bool trim;
bool lowerCase;
bool upperCase;
```
###### trim: `bool`
- Removes any leading and trailing whitespace from the input value
- Use `rule.value` for the trimmed value
```dart
import 'package:rules/src/models/rule_options.dart';
void main() {
final rule1 = Rule(
' ',
name: 'Name',
isRequired: true,
options: RuleOptions(
trim: true,
),
);
print(rule1.hasError);
// output: true
print(rule1.value);
// output:
final rule2 = Rule(
' abc@xyz.com ',
name: 'Email',
isEmail: true,
options: RuleOptions(
trim: true,
),
);
print(rule2.hasError);
// output: false
print(rule2.value);
// output: abc@xyz.com
}
```
###### lowercase: `bool`
- Converts all characters, in the input string, to lower case
- Use `rule.value` for the converted value
```dart
import 'package:rules/src/models/rule_options.dart';
void main() {
final rule = Rule(
'ABC',
name: 'Input field',
regex: RegExp('[a-z]'),
options: RuleOptions(
lowerCase: true,
),
);
print(rule.hasError);
// output: false
print(rule.value);
// output: abc
}
```
###### upperCase: `bool`
- Converts all characters, in the input string, to upper case
- Use `rule.value` for the converted value
```dart
import 'package:rules/src/models/rule_options.dart';
void main() {
final rule = Rule(
'xyz',
name: 'Input field',
regex: RegExp('[A-Z]'),
options: RuleOptions(
upperCase: true,
),
);
print(rule.hasError);
// output: false
print(rule.value);
// output: xyz
}
```
**Extension**
- Extend and override the constraints of a group rule using 'copyWith' method.
- The child rule will default to the constraint values of the parent unless they are set explicitly in the child.
```dart
void main() {
const textFieldValue1 = 'abc';
const textFieldValue2 = '';
final rule1 = Rule(
textFieldValue1,
name: 'Text field',
isRequired: true,
); // Validation OK
final rule2 = Rule(
textFieldValue2,
name: 'Text field',
); // Validation OK
// parent
final groupRule1 = GroupRule(
[rule1, rule2],
name: 'Group name 1',
requiredAll: true,
customErrorText: 'Invalid input for Group 1',
); // Validation FAILED
// child
final groupRule2 = groupRule1.copyWith(
name: 'Group name 2',
requiredAll: false,
customErrorText: 'Invalid input for Group 2',
); // Validation OK
print(groupRule1.error);
// output: Invalid input for Group 1
print(groupRule2.error);
// output: null
}
```
```dart
void main() {
const textFieldValue1 = 'abc';
final rule1 = Rule(
textFieldValue1,
name: 'Text field',
isRequired: true,
); // Validation OK
final rule2 = rule1.copyWith(
name: 'Text field',
); // Validation OK
// parent
final groupRule1 = GroupRule(
[rule1, rule2],
name: 'Group name 1',
requiredAll: true,
customErrorText: 'Invalid input for Group 1',
); // Validation OK
// child
final groupRule2 = groupRule1.copyWith(
name: 'Group name 2',
requiredAll: false,
customErrorText: 'Invalid input for Group 2',
); // Validation OK
print(groupRule1.error);
// output: null
print(groupRule2.error);
// output: null
}
```
#### 3. CombinedRule
Manage multiple Rules and GroupRules
- Both 'Rule' and/or 'GroupRule' are accepted as inputs.
- Errors of both 'Rule' and 'GroupRule', if any, are combined into a list.
- Order of appearance of error texts in CombinedRule errorList:
1. Rule
2. GroupRule
**Basic example**
```dart
void main() {
const textFieldValue1 = '';
const textFieldValue2 = 'abc@xyz.com';
final rule1 = Rule(
textFieldValue1,
name: 'Text field 1',
); // Validation OK
final rule2 = Rule(
textFieldValue2,
name: 'Text field 2',
isEmail: true,
); // Validation OK
final groupRule = GroupRule([rule1, rule2],
name: 'Group name', requiredAll: true); // Validation FAILED
const textFieldValue3 = '';
final rule3 = Rule(
textFieldValue3,
name: 'Text field 3',
isRequired: true,
); // Validation FAILED
final combinedRule = CombinedRule(
rules: [rule3],
groupRules: [groupRule],
);
print(combinedRule.errorList);
// output: ['Text field 3 is required', 'All fields are mandatory in Group name']
print(combinedRule.hasError);
// output: true
if (combinedRule.hasError) {
// some action on error
} else {
// Some action on success
}
}
```
**Available fields**
```dart
List rules;
List groupRules;
```
###### rules: `List`
```dart
void main() {
const textFieldValue1 = '';
const textFieldValue2 = 'abc@xyz';
const textFieldValue3 = '';
final rule1 = Rule(
textFieldValue1,
name: 'Text field 1',
); // Validation OK
final rule2 = Rule(
textFieldValue2,
name: 'Text field 2',
isEmail: true,
); // Validation FAILED
final rule3 = Rule(
textFieldValue3,
name: 'Text field 3',
isRequired: true,
customErrorText: 'Invalid field input',
); // Validation FAILED
final combinedRule = CombinedRule(
rules: [rule1, rule2, rule3],
);
print(combinedRule.errorList);
// output: ['Text field 2 is not a valid email address', 'Invalid field input']
print(combinedRule.hasError);
// output: true
}
```
###### groupRules: `List`
```dart
void main() {
const textFieldValue1 = '';
const textFieldValue2 = 'abc@xyz';
final rule1 = Rule(
textFieldValue1,
name: 'Text field 1',
); // Validation OK
final rule2 = Rule(
textFieldValue2,
name: 'Text field 2',
isEmail: true,
); // Validation FAILED
final groupRule1 = GroupRule(
[rule1, rule2],
name: 'Group name',
requiredAll: true,
customErrorText: 'Invalid input',
); // Validation FAILED
final groupRule2 = GroupRule(
[],
name: 'Group name',
); // Validation OK
final combinedRule = CombinedRule(
groupRules: [groupRule1, groupRule2],
);
print(combinedRule.errorList);
// output: ['Invalid input']
print(combinedRule.hasError);
// output: true
}
```
#### Flutter
```dart
class _MyStatefulWidgetState extends State {
String emailInput;
String phoneInput;
void _handleEmailTextFieldOnChange(String value) {
setState(() {
emailInput = value;
});
}
void _handlePhoneTextFieldOnChange(String value) {
setState(() {
phoneInput = value;
});
}
Rule get emailInputRule {
return Rule(
emailInput,
name: 'Email',
isAlphaSpace: true,
isRequired: true,
customErrorText: 'Invalid Email',
);
}
Rule get phoneInputRule {
return Rule(
phoneInput,
name: 'Phone',
isPhone: true,
isRequired: true,
customErrorText: 'Invalid Phone',
);
}
bool get isContinueBtnEnabled {
final groupRule = GroupRule(
[emailInputRule, phoneInputRule],
name: 'Continue Button',
requiredAll: true,
);
return !groupRule.hasError;
}
Widget build(BuildContext context) {
return Scaffold(
body: Center(
child: Column(
children: [
TextField(
onChanged: (String value) {
_handleEmailTextFieldOnChange(value);
},
decoration: InputDecoration(
hintText: 'Email address',
errorText: emailInputRule?.error ?? null,
),
),
TextField(
onChanged: (String value) {
_handlePhoneTextFieldOnChange(value);
},
decoration: InputDecoration(
hintText: 'Phone',
errorText: phoneInputRule?.error ?? null,
),
),
if (isContinueBtnEnabled)
FlatButton(
onPressed: () {
// call api
},
child: const Text('Continue'),
)
else
Container()
],
),
),
);
}
}
```
#### Flutter Mobx
Mobx Store
```dart
class UpdateUserStore = _UpdateUserStoreBase
with _$UpdateUserStore;
abstract class _UpdateUserStoreBase with Store {
@observable
String profileName;
@observable
String profileEmail;
@computed
Rules get profileNameInputRule {
final rule = Rules(
profileName,
name: 'Name',
isRequired: false,
isAlphaSpace: true,
customErrorText: 'Invalid name',
);
return rule;
}
@computed
Rules get profileEmailInputRule {
final rule = Rules(
profileEmail,
name: 'Name',
isRequired: false,
isEmail: true,
customErrorText: 'Invalid email',
);
return rule;
}
@computed
bool get isContinueButtonEnabled {
final groupRule = GroupRules(
[profileEmailInputRule, profileNameInputRule],
name: 'Continue Button',
requiredAll: true,
);
return !groupRule.hasError;
}
@action
void setProfileName(String value) {
profileName = value;
}
@action
void setProfileEmail(String value) {
profileEmail = value;
}
}
```
Widget
```dart
class _UpdateUserScreen extends State {
UpdateUserStore _updateUserStore = UpdateUserStore();
void _handleProfileNameOnChange(String value) {
_updateUserStore.setProfileName(value);
}
void _handleProfileEmailOnChange(String value) {
_updateUserStore.setProfileEmail(value);
}
@override
Widget build(BuildContext context) {
return Container(
width: Display.getWidth(context),
height: Display.getHeight(context),
child: Column(
mainAxisAlignment: MainAxisAlignment.end,
children: [
Observer(
builder: (_) {
final _errorText = _updateUserStore.profileNameInputRule?.error;
return TextField(
onChanged: (String value) {
_handleProfileNameOnChange(value);
},
decoration: InputDecoration(
hintText: 'Name',
errorText: _errorText,
),
);
},
),
Observer(
builder: (_) {
final _errorText = _updateUserStore.profileEmailInputRule?.error;
return TextField(
onChanged: (String value) {
_handleProfileEmailOnChange(value);
},
decoration: InputDecoration(
hintText: 'Email',
errorText: _errorText,
),
);
},
),
Observer(
builder: (_) {
final _isContinueButtonEnabled =
_updateUserStore.isContinueButtonEnabled;
if (!_isContinueButtonEnabled) {
return Container();
}
return FlatButton(
onPressed: () {},
child: const Text('Continue'),
);
},
),
],
),
);
}
}
```
### Changelogs
##### 2.0.0
New feature:
- Null safety
- Added `shouldPass`
##### 1.2.0+1
New feature:
- Added `trim`, `upperCase` and `lowerCase` rule **options**
##### 1.1.0
Breaking changes:
- `regex` now expects a RegExp object instead of String
### Buy me a coffee
Help me keep the app FREE and open for all.
Paypal me: [paypal.me/ganeshrvel](https://paypal.me/ganeshrvel "paypal.me/ganeshrvel")
### Contacts
Please feel free to contact me at ganeshrvel@outlook.com
### About
- Author: [Ganesh Rathinavel](https://www.linkedin.com/in/ganeshrvel "Ganesh Rathinavel")
- License: [MIT](https://github.com/ganeshrvel/openmtp/blob/master/LICENSE "MIT")
- Package URL: [https://pub.dev/packages/rules](https://pub.dev/packages/rules "https://pub.dev/packages/rules")
- Repo URL: [https://github.com/ganeshrvel/pub-rules](https://github.com/ganeshrvel/pub-rules/ "https://github.com/ganeshrvel/pub-rules")
- Contacts: ganeshrvel@outlook.com
### License
Rules | Powerful and feature-rich validation library for both Dart and Flutter. [MIT License](https://github.com/ganeshrvel/pub-rules/blob/master/LICENSE "MIT License").
Copyright © 2018 - Present Ganesh Rathinavel