master_validator

Description:

master validator

master_validator #



Live Demo #
Documentation #
Simple and quick form validation library for Flutter.

Easy to get started with
Lightweight
Customizable Error Messages
Validator Chaining



View New Documentation #
Documentation #
Getting Started #
Installation #
Add master_validator as dependency to your flutter project by running the following command in project-root.
flutter pub add master_validator
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Then run flutter pub get to install required dependencies.
Check installation tab for more information
Code #
Import master_validator package to your dart widgets by writing:
import 'package:master_validator/master_validator.dart';
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This makes the Validators class available in your codespace
Basic Required Field Validation #
Use Validators.Required() to make a field required.
TextFormField(
validator: Validators.Required(
errorMessage : "This field cannot be left empty",
)
),
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Email Validation #
TextFormField(
validator: Validators.Required(
next : Validators.Email(),
),
),
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Inbuild Validation methods : #

Validators.Required()
Validators.Email()
Validators.Number()

with optional integerOnly allowNegative allowDecimal parameters


Validators.LengthBetween()
Validators.Minlength()
Validators.Maxlength()
Validators.Url()
Validators.Regex()
Validators.Equals()
Validators.FileName()
Validators.DirectoryName()

Every validator has an errorMessage parameter to customize the error message and a next parameter to chain another validator
Using Multiple Validators (Chaining Validators) #
All validators take a next argument in which you can specify another validator (a custom function, or another predefined validator) like :
TextFormField(
validator: Validators.Required(
next : Validators.Email(
next : Validators.Maxlength(50)
),
),
),
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Note: While Chaining, Order MATTERS!


NOTE: By default All Validators except Validators.Required() will not throw an error if the data is empty/null, this means if you defined a validator like :

TextFormField(
validator: Validators.Email(),
),
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It means the field acts as an optional field but if something is entered it must qualify as an email, to change this behaviour, and to make the field required, use Validators.Required() before any other validator, for example -

TextFormField(
validator: Validators.Required(
next : Validators.Url(),
),
),
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For detailed usage, check example/lib