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String Decorator ​

The String decorator is used to apply validations to string properties within classes in TypeScript, ensuring that data meets certain specified criteria before being processed or stored.

Properties ​

  • minLength: number - Specifies the minimum length the string must be.
  • maxLength: number - Defines the maximum length allowed for the string.
  • regexPattern: RegExp - A regular expression pattern that the string must conform to.

Usage ​

To use the String decorator, you must first make sure your project is configured to use decorators in TypeScript.

Basic Example ​

typescript
import { ClassValidator, String } from "rest-data-validator";

@ClassValidator
class Post {
  @String({ minLength: 10, maxLength: 100 })
  title: string;

  @String({ regexPattern: /^[a-zA-Z0-9 ]+$/ })
  content: string;
}

In this example, title must be between 10 and 100 characters, while content must match the specified pattern and cannot be empty.

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