Validator
一个接口，实现了它的类可以扮演验证器的角色。
An interface implemented by classes that perform synchronous validation.
interface Validator {
validate(control: AbstractControl): ValidationErrors | null
registerOnValidatorChange(fn: () => void)?: void
}
子接口
方法
Method that performs synchronous validation against the provided control. | |||
参数
返回值
|
Registers a callback function to call when the validator inputs change. |
使用说明
提供一个自定义的验证器
Provide a custom validator
下面的例子实现了 Validator 接口，以便用一个自定义的错误键来创建验证器指令。
The following example implements the Validator interface to create a validator directive with a custom error key.
@Directive({
selector: '[customValidator]',
providers: [{provide: NG_VALIDATORS, useExisting: CustomValidatorDirective, multi: true}]
})
class CustomValidatorDirective implements Validator {
validate(control: AbstractControl): ValidationErrors|null {
return {'custom': true};
}
}
