表单和字段验证

TanStack Form 功能的核心是验证概念。TanStack Form 使验证高度可定制:

  • 您可以控制何时执行验证(在更改时、输入时、失焦时、提交时...)
  • 验证规则可以在字段级别或表单级别定义
  • 验证可以是同步的或异步的(例如,作为 API 调用的结果)

何时执行验证?

这取决于您![tanstackField] 指令接受一些回调作为属性,如 onChangeonBlur。这些回调会传递字段的当前值以及 fieldAPI 对象,以便您可以执行验证。如果您发现验证错误,只需将错误消息作为字符串返回,它将在 field.api.state.meta.errors 中可用。

这是一个示例:

angular-ts
@Component({
  selector: 'app-root',
  standalone: true,
  imports: [TanStackField],
  template: `
    <ng-container
      [tanstackField]="form"
      name="age"
      [validators]="{
        onChange: ageValidator
      }"
      #age="field"
    >
      <label [for]="age.api.name">年龄:</label>
      <input
        [id]="age.api.name"
        [name]="age.api.name"
        [value]="age.api.state.value"
        type="number"
        (input)="age.api.handleChange($any($event).target.valueAsNumber)"
      />
      @if (age.api.state.meta.errors) {
        <em role="alert">{{ age.api.state.meta.errors.join(', ') }}</em>
      }
    </ng-container>
  `,
})
export class AppComponent {
  ageValidator: FieldValidateFn<any, any, any, any, number> = ({ value }) =>
    value < 13 ? '您必须年满 13 岁才能创建账户' : undefined

  // ...
}
@Component({
  selector: 'app-root',
  standalone: true,
  imports: [TanStackField],
  template: `
    <ng-container
      [tanstackField]="form"
      name="age"
      [validators]="{
        onChange: ageValidator
      }"
      #age="field"
    >
      <label [for]="age.api.name">年龄:</label>
      <input
        [id]="age.api.name"
        [name]="age.api.name"
        [value]="age.api.state.value"
        type="number"
        (input)="age.api.handleChange($any($event).target.valueAsNumber)"
      />
      @if (age.api.state.meta.errors) {
        <em role="alert">{{ age.api.state.meta.errors.join(', ') }}</em>
      }
    </ng-container>
  `,
})
export class AppComponent {
  ageValidator: FieldValidateFn<any, any, any, any, number> = ({ value }) =>
    value < 13 ? '您必须年满 13 岁才能创建账户' : undefined

  // ...
}

在上面的示例中,验证在每次按键时执行(onChange)。如果我们希望在字段失焦时执行验证,我们会像这样更改上面的代码:

angular-ts
@Component({
  selector: 'app-root',
  standalone: true,
  imports: [TanStackField],
  template: `
    <ng-container
      [tanstackField]="form"
      name="age"
      [validators]="{
        onBlur: ageValidator
      }"
      #age="field"
    >
      <label [for]="age.api.name">年龄:</label>
      <!-- 我们始终需要实现 onChange,以便 TanStack Form 接收更改 -->
      <!-- 监听字段上的 onBlur 事件 -->
      <input
        [id]="age.api.name"
        [name]="age.api.name"
        [value]="age.api.state.value"
        type="number"
        (blur)='age.api.handleBlur()'
        (input)="age.api.handleChange($any($event).target.valueAsNumber)"
      />
      @if (age.api.state.meta.errors) {
        <em role="alert">{{ age.api.state.meta.errors.join(', ') }}</em>
      }
    </ng-container>
  `,
})
export class AppComponent {
  ageValidator: FieldValidateFn<any, any, any, any, number> = ({ value }) =>
    value < 13 ? '您必须年满 13 岁才能创建账户' : undefined

  // ...
}
@Component({
  selector: 'app-root',
  standalone: true,
  imports: [TanStackField],
  template: `
    <ng-container
      [tanstackField]="form"
      name="age"
      [validators]="{
        onBlur: ageValidator
      }"
      #age="field"
    >
      <label [for]="age.api.name">年龄:</label>
      <!-- 我们始终需要实现 onChange,以便 TanStack Form 接收更改 -->
      <!-- 监听字段上的 onBlur 事件 -->
      <input
        [id]="age.api.name"
        [name]="age.api.name"
        [value]="age.api.state.value"
        type="number"
        (blur)='age.api.handleBlur()'
        (input)="age.api.handleChange($any($event).target.valueAsNumber)"
      />
      @if (age.api.state.meta.errors) {
        <em role="alert">{{ age.api.state.meta.errors.join(', ') }}</em>
      }
    </ng-container>
  `,
})
export class AppComponent {
  ageValidator: FieldValidateFn<any, any, any, any, number> = ({ value }) =>
    value < 13 ? '您必须年满 13 岁才能创建账户' : undefined

  // ...
}

因此,您可以通过实现所需的回调来控制何时执行验证。您甚至可以在不同时间执行不同的验证:

angular-ts
@Component({
  selector: 'app-root',
  standalone: true,
  imports: [TanStackField],
  template: `
    <ng-container
      [tanstackField]="form"
      name="age"
      [validators]="{
        onChange: ageValidator,
        onBlur: minimumAgeValidator
      }"
      #age="field"
    >
      <label [for]="age.api.name">年龄:</label>
      <!-- 我们始终需要实现 onChange,以便 TanStack Form 接收更改 -->
      <!-- 监听字段上的 onBlur 事件 -->
      <input
        [id]="age.api.name"
        [name]="age.api.name"
        [value]="age.api.state.value"
        type="number"
        (blur)="age.api.handleBlur()"
        (input)="age.api.handleChange($any($event).target.valueAsNumber)"
      />
      @if (!age.api.state.meta.isValid) {
        <em role="alert">{{ age.api.state.meta.errors.join(', ') }}</em>
      }
    </ng-container>
  `,
})
export class AppComponent {
  ageValidator: FieldValidateFn<any, any, any, any, number> = ({ value }) =>
    value < 13 ? '您必须年满 13 岁才能创建账户' : undefined

  minimumAgeValidator: FieldValidateFn<any, any, any, any, number> = ({
    value,
  }) => (value < 0 ? '无效值' : undefined)

  // ...
}
@Component({
  selector: 'app-root',
  standalone: true,
  imports: [TanStackField],
  template: `
    <ng-container
      [tanstackField]="form"
      name="age"
      [validators]="{
        onChange: ageValidator,
        onBlur: minimumAgeValidator
      }"
      #age="field"
    >
      <label [for]="age.api.name">年龄:</label>
      <!-- 我们始终需要实现 onChange,以便 TanStack Form 接收更改 -->
      <!-- 监听字段上的 onBlur 事件 -->
      <input
        [id]="age.api.name"
        [name]="age.api.name"
        [value]="age.api.state.value"
        type="number"
        (blur)="age.api.handleBlur()"
        (input)="age.api.handleChange($any($event).target.valueAsNumber)"
      />
      @if (!age.api.state.meta.isValid) {
        <em role="alert">{{ age.api.state.meta.errors.join(', ') }}</em>
      }
    </ng-container>
  `,
})
export class AppComponent {
  ageValidator: FieldValidateFn<any, any, any, any, number> = ({ value }) =>
    value < 13 ? '您必须年满 13 岁才能创建账户' : undefined

  minimumAgeValidator: FieldValidateFn<any, any, any, any, number> = ({
    value,
  }) => (value < 0 ? '无效值' : undefined)

  // ...
}

在上面的示例中,我们在不同时间对同一字段验证不同的内容(在每次按键时和字段失焦时)。由于 field.state.meta.errors 是一个数组,因此会显示给定时间的所有相关错误。您还可以使用 field.state.meta.errorMap 根据验证执行的_时间_(onChange、onBlur 等)获取错误。有关显示错误的更多信息请参见下文。

显示错误

一旦您设置了验证,您可以将错误从数组映射到 UI 中显示:

angular-ts
@Component({
  selector: 'app-root',
  standalone: true,
  imports: [TanStackField],
  template: `
    <ng-container
      [tanstackField]="form"
      name="age"
      [validators]="{
        onChange: ageValidator
      }"
      #age="field"
    >
      <!-- ... -->
      @if (age.api.state.meta.errors) {
        <em role="alert">{{ age.api.state.meta.errors.join(', ') }}</em>
      }
    </ng-container>
  `,
})
export class AppComponent {
  ageValidator: FieldValidateFn<any, any, any, any, number> = ({ value }) =>
    value < 13 ? '您必须年满 13 岁才能创建账户' : undefined

  // ...
}
@Component({
  selector: 'app-root',
  standalone: true,
  imports: [TanStackField],
  template: `
    <ng-container
      [tanstackField]="form"
      name="age"
      [validators]="{
        onChange: ageValidator
      }"
      #age="field"
    >
      <!-- ... -->
      @if (age.api.state.meta.errors) {
        <em role="alert">{{ age.api.state.meta.errors.join(', ') }}</em>
      }
    </ng-container>
  `,
})
export class AppComponent {
  ageValidator: FieldValidateFn<any, any, any, any, number> = ({ value }) =>
    value < 13 ? '您必须年满 13 岁才能创建账户' : undefined

  // ...
}

或使用 errorMap 属性访问您要查找的特定错误:

angular-ts
@Component({
  selector: 'app-root',
  standalone: true,
  imports: [TanStackField],
  template: `
    <ng-container
      [tanstackField]="form"
      name="age"
      [validators]="{
        onChange: ageValidator
      }"
      #age="field"
    >
      <!-- ... -->
      @if (age.api.state.meta.errorMap['onChange']) {
        <em role="alert">{{ age.api.state.meta.errorMap['onChange'] }}</em>
      }
    </ng-container>
  `,
})
export class AppComponent {
  ageValidator: FieldValidateFn<any, any, any, any, number> = ({ value }) =>
    value < 13 ? '您必须年满 13 岁才能创建账户' : undefined

  // ...
}
@Component({
  selector: 'app-root',
  standalone: true,
  imports: [TanStackField],
  template: `
    <ng-container
      [tanstackField]="form"
      name="age"
      [validators]="{
        onChange: ageValidator
      }"
      #age="field"
    >
      <!-- ... -->
      @if (age.api.state.meta.errorMap['onChange']) {
        <em role="alert">{{ age.api.state.meta.errorMap['onChange'] }}</em>
      }
    </ng-container>
  `,
})
export class AppComponent {
  ageValidator: FieldValidateFn<any, any, any, any, number> = ({ value }) =>
    value < 13 ? '您必须年满 13 岁才能创建账户' : undefined

  // ...
}

值得一提的是,我们��� errors 数组和 errorMap 与验证器返回的类型匹配。这意味着:

angular-ts
@Component({
  selector: 'app-root',
  standalone: true,
  imports: [TanStackField],
  template: `
    <ng-container
      [tanstackField]="form"
      name="age"
      [validators]="{
        onChange: ageValidator
      }"
      #age="field"
    >
      <!-- ... -->
      <!-- errorMap.onChange is type `{isOldEnough: false} | undefined` -->
      <!-- meta.errors is type `Array<{isOldEnough: false} | undefined>` -->
      @if (!age.api.state.meta.errorMap['onChange']?.isOldEnough) {
        <em role="alert">用户年龄不够</em>
      }
    </ng-container>
  `,
})
export class AppComponent {
  ageValidator: FieldValidateFn<any, any, any, any, number> = ({ value }) =>
    value < 13 ? '您必须年满 13 岁才能创建账户' : undefined

  // ...
}
@Component({
  selector: 'app-root',
  standalone: true,
  imports: [TanStackField],
  template: `
    <ng-container
      [tanstackField]="form"
      name="age"
      [validators]="{
        onChange: ageValidator
      }"
      #age="field"
    >
      <!-- ... -->
      <!-- errorMap.onChange is type `{isOldEnough: false} | undefined` -->
      <!-- meta.errors is type `Array<{isOldEnough: false} | undefined>` -->
      @if (!age.api.state.meta.errorMap['onChange']?.isOldEnough) {
        <em role="alert">用户年龄不够</em>
      }
    </ng-container>
  `,
})
export class AppComponent {
  ageValidator: FieldValidateFn<any, any, any, any, number> = ({ value }) =>
    value < 13 ? '您必须年满 13 岁才能创建账户' : undefined

  // ...
}

字段级别与表单级别的验证

如上所示,每个 [tanstackField] 通过 onChangeonBlur 等回调接受自己的验证规则。也可以通过向 injectForm() 函数传递类似的回调来在表单级别(而不是逐个字段)定义验证规则。

示例:

angular-ts
@Component({
  selector: 'app-root',
  standalone: true,
  imports: [TanStackField],
  template: `
    <div>
      <ng-container [tanstackField]="form" name="age" #age="field">
        <!-- ... -->
        @if (formErrorMap().onChange) {
          <div>
            <em
              >表单出现错误:{{ formErrorMap().onChange }}</em
            >
          </div>
        }
        <!-- ... -->
      </ng-container>
    </div>
  `,
})
export class AppComponent {
  form = injectForm({
    defaultValues: {
      age: 0,
    },
    onSubmit({ value }) {
      console.log(value)
    },
    validators: {
      // 以与向字段添加验证器相同的方式向表单添加验证器
      onChange({ value }) {
        if (value.age < 13) {
          return '必须年满 13 岁才能注册'
        }
        return undefined
      },
    },
  })

  // 订阅表单的错误映射,以便对其的更新会渲染
  formErrorMap = injectStore(this.form, (state) => state.errorMap)
}
@Component({
  selector: 'app-root',
  standalone: true,
  imports: [TanStackField],
  template: `
    <div>
      <ng-container [tanstackField]="form" name="age" #age="field">
        <!-- ... -->
        @if (formErrorMap().onChange) {
          <div>
            <em
              >表单出现错误:{{ formErrorMap().onChange }}</em
            >
          </div>
        }
        <!-- ... -->
      </ng-container>
    </div>
  `,
})
export class AppComponent {
  form = injectForm({
    defaultValues: {
      age: 0,
    },
    onSubmit({ value }) {
      console.log(value)
    },
    validators: {
      // 以与向字段添加验证器相同的方式向表单添加验证器
      onChange({ value }) {
        if (value.age < 13) {
          return '必须年满 13 岁才能注册'
        }
        return undefined
      },
    },
  })

  // 订阅表单的错误映射,以便对其的更新会渲染
  formErrorMap = injectStore(this.form, (state) => state.errorMap)
}

从表单验证器设置字段级别错误

您可以从表单的验证器在字段上设置错误。一个常见的用例是通过在表单的 onSubmitAsync 验证器中调用单个 API 端点来在提交时验证所有字段。

angular-ts
@Component({
  selector: 'app-root',
  imports: [TanStackField],
  template: `
    <form (submit)="handleSubmit($event)">
      <div>
        <ng-container
          [tanstackField]="form"
          name="age"
          #ageField="field"
        >
          <label [for]="ageField.api.name">年龄:</label>
          <input
            type="number"
            [name]="ageField.api.name"
            [value]="ageField.api.state.value"
            (blur)="ageField.api.handleBlur()"
            (input)="ageField.api.handleChange($any($event).target.valueAsNumber)"
          />
          @if (ageField.api.state.meta.errors.length > 0) {
            <em role="alert">{{ ageField.api.state.meta.errors.join(', ') }}</em>
          }
        </ng-container>
      </div>
      <button type="submit">提交</button>
    </form>
  `,
})

export class AppComponent {
  form = injectForm({
    defaultValues: {
      age: 0,
      socials: [],
      details: {
        email: '',
      },
    },
    validators: {
      onSubmitAsync: async ({ value }) => {
        // 在服务器上验证值
        const hasErrors = await verifyDataOnServer(value)
        if (hasErrors) {
          return {
            form: '无效数据', // `form` 键是可选的
            fields: {
              age: '必须年满 13 岁才能注册',
              // 使用字段名称在嵌套字段上设置错误
              'socials[0].url': '提供的 URL 不存在',
              'details.email': '需要电子邮件',
            },
          };
        }

        return null;
      },
    },
  });

  handleSubmit(event: SubmitEvent) {
    event.preventDefault();
    event.stopPropagation();
    this.form.handleSubmit();
  }
}
@Component({
  selector: 'app-root',
  imports: [TanStackField],
  template: `
    <form (submit)="handleSubmit($event)">
      <div>
        <ng-container
          [tanstackField]="form"
          name="age"
          #ageField="field"
        >
          <label [for]="ageField.api.name">年龄:</label>
          <input
            type="number"
            [name]="ageField.api.name"
            [value]="ageField.api.state.value"
            (blur)="ageField.api.handleBlur()"
            (input)="ageField.api.handleChange($any($event).target.valueAsNumber)"
          />
          @if (ageField.api.state.meta.errors.length > 0) {
            <em role="alert">{{ ageField.api.state.meta.errors.join(', ') }}</em>
          }
        </ng-container>
      </div>
      <button type="submit">提交</button>
    </form>
  `,
})

export class AppComponent {
  form = injectForm({
    defaultValues: {
      age: 0,
      socials: [],
      details: {
        email: '',
      },
    },
    validators: {
      onSubmitAsync: async ({ value }) => {
        // 在服务器上验证值
        const hasErrors = await verifyDataOnServer(value)
        if (hasErrors) {
          return {
            form: '无效数据', // `form` 键是可选的
            fields: {
              age: '必须年满 13 岁才能注册',
              // 使用字段名称在嵌套字段上设置错误
              'socials[0].url': '提供的 URL 不存在',
              'details.email': '需要电子邮件',
            },
          };
        }

        return null;
      },
    },
  });

  handleSubmit(event: SubmitEvent) {
    event.preventDefault();
    event.stopPropagation();
    this.form.handleSubmit();
  }
}

值得一提的是,如果您有一个返回错误的表单验证函数,该错误可能会被字段特定的验证覆盖。

这意味着:

angular-ts
@Component({
  selector: 'app-root',
  standalone: true,
  imports: [TanStackField],
  template: `
      <div>
        <ng-container
         [tanstackField]="form"
        name="age"
       #ageField="field"
      [validators]="{
       onChange: fieldValidator
    }"
 >
  <input type="number" [value]="ageField.api.state.value"
  (input)="ageField.api.handleChange($any($event).target.valueAsNumber)"
  />
   @if (ageField.api.state.meta.errors.length > 0) {
      <em role="alert">{{ ageField.api.state.meta.errors.join(', ') }}</em>
    }
  </ng-container>
</div>
`,
})
export class AppComponent {
  form = injectForm({
    defaultValues: {
      age: 0,
    },
    validators: {
      onChange: ({ value }) => {
        return {
          fields: {
            age: value.age < 12 ? 'Too young!' : undefined,
          },
        };
      },
    },
  });

  fieldValidator: FieldValidateFn<any, any, number> = ({ value }) =>
    value % 2 === 0 ? 'Must be odd!' : undefined;
}
@Component({
  selector: 'app-root',
  standalone: true,
  imports: [TanStackField],
  template: `
      <div>
        <ng-container
         [tanstackField]="form"
        name="age"
       #ageField="field"
      [validators]="{
       onChange: fieldValidator
    }"
 >
  <input type="number" [value]="ageField.api.state.value"
  (input)="ageField.api.handleChange($any($event).target.valueAsNumber)"
  />
   @if (ageField.api.state.meta.errors.length > 0) {
      <em role="alert">{{ ageField.api.state.meta.errors.join(', ') }}</em>
    }
  </ng-container>
</div>
`,
})
export class AppComponent {
  form = injectForm({
    defaultValues: {
      age: 0,
    },
    validators: {
      onChange: ({ value }) => {
        return {
          fields: {
            age: value.age < 12 ? 'Too young!' : undefined,
          },
        };
      },
    },
  });

  fieldValidator: FieldValidateFn<any, any, number> = ({ value }) =>
    value % 2 === 0 ? 'Must be odd!' : undefined;
}

即使表单级别验证返回 'Too young!' 错误,也只会显示 'Must be odd!

异步函数验证

虽然我们认为大多数验证都是同步的,但在许多情况下,网络调用或其他异步操作对验证很有用。

为此,我们有专门的 onChangeAsynconBlurAsync 和其他可用于验证的方法:

angular-ts
@Component({
  selector: 'app-root',
  standalone: true,
  imports: [TanStackField],
  template: `
    <ng-container
      [tanstackField]="form"
      name="age"
      [validators]="{ onChangeAsync: ageValidator }"
      #age="field"
    >
      <label [for]="age.api.name">姓氏:</label>
      <input
        [id]="age.api.name"
        [name]="age.api.name"
        [value]="age.api.state.value"
        type="number"
        (input)="age.api.handleChange($any($event).target.valueAsNumber)"
      />
      @if (age.api.state.meta.errors) {
        <em role="alert">{{ age.api.state.meta.errors.join(', ') }}</em>
      }
    </ng-container>
  `,
})
export class AppComponent {
  ageValidator: FieldValidateAsyncFn<any, string, number> = async ({
    value,
  }) => {
    await new Promise((resolve) => setTimeout(resolve, 1000))
    return value < 13 ? '您必须年满 13 岁才能创建账户' : undefined
  }

  // ...
}
@Component({
  selector: 'app-root',
  standalone: true,
  imports: [TanStackField],
  template: `
    <ng-container
      [tanstackField]="form"
      name="age"
      [validators]="{ onChangeAsync: ageValidator }"
      #age="field"
    >
      <label [for]="age.api.name">姓氏:</label>
      <input
        [id]="age.api.name"
        [name]="age.api.name"
        [value]="age.api.state.value"
        type="number"
        (input)="age.api.handleChange($any($event).target.valueAsNumber)"
      />
      @if (age.api.state.meta.errors) {
        <em role="alert">{{ age.api.state.meta.errors.join(', ') }}</em>
      }
    </ng-container>
  `,
})
export class AppComponent {
  ageValidator: FieldValidateAsyncFn<any, string, number> = async ({
    value,
  }) => {
    await new Promise((resolve) => setTimeout(resolve, 1000))
    return value < 13 ? '您必须年满 13 岁才能创建账户' : undefined
  }

  // ...
}

同步和异步验证可以共存。例如,可以在同一字段上定义 onBluronBlurAsync

angular-ts
@Component({
  selector: 'app-root',
  standalone: true,
  imports: [TanStackField],
  template: `
    <ng-container
      [tanstackField]="form"
      name="age"
      [validators]="{ onBlur: ensureAge13, onBlurAsync: ensureOlderAge }"
      #age="field"
    >
      <label [for]="age.api.name">姓氏:</label>
      <input
        [id]="age.api.name"
        [name]="age.api.name"
        [value]="age.api.state.value"
        type='number'
        (blur)="age.api.handleBlur()"
        (input)="age.api.handleChange($any($event).target.value)"
      />
      @if (age.api.state.meta.errors) {
        <em role="alert">{{ age.api.state.meta.errors.join(', ') }}</em>
      }
    </ng-container>
  `,
})
export class AppComponent {
  ensureAge13: FieldValidateFn<any, any, any, any, number> = ({ value }) =>
    value < 13 ? '您必须至少年满 13 岁' : undefined

  ensureOlderAge: FieldValidateAsyncFn<any, string, number> = async ({
    value,
  }) => {
    const currentAge = await fetchCurrentAgeOnProfile()
    return value < currentAge ? '您只能增加年龄' : undefined
  }

  // ...
}
@Component({
  selector: 'app-root',
  standalone: true,
  imports: [TanStackField],
  template: `
    <ng-container
      [tanstackField]="form"
      name="age"
      [validators]="{ onBlur: ensureAge13, onBlurAsync: ensureOlderAge }"
      #age="field"
    >
      <label [for]="age.api.name">姓氏:</label>
      <input
        [id]="age.api.name"
        [name]="age.api.name"
        [value]="age.api.state.value"
        type='number'
        (blur)="age.api.handleBlur()"
        (input)="age.api.handleChange($any($event).target.value)"
      />
      @if (age.api.state.meta.errors) {
        <em role="alert">{{ age.api.state.meta.errors.join(', ') }}</em>
      }
    </ng-container>
  `,
})
export class AppComponent {
  ensureAge13: FieldValidateFn<any, any, any, any, number> = ({ value }) =>
    value < 13 ? '您必须至少年满 13 岁' : undefined

  ensureOlderAge: FieldValidateAsyncFn<any, string, number> = async ({
    value,
  }) => {
    const currentAge = await fetchCurrentAgeOnProfile()
    return value < currentAge ? '您只能增加年龄' : undefined
  }

  // ...
}

同步验证方法(onBlur)首先运行,异步方法(onBlurAsync)仅在同步方法(onBlur)成功时运行。要更改此行为,请将 asyncAlways 选项设置为 true,异步方法将无论同步方法的结果如何都会运行。

内置防抖

虽然在对数据库进行验证时异步调用是正确的方法,但在每次按键时运行网络请求是对数据库进行 DDOS 攻击的好方法。

相反,我们通过添加单个属性来启用对 async 调用进行防抖的简单方法:

angular-html
<ng-container
  [tanstackField]="form"
  name="age"
  asyncDebounceMs={500}
  [validators]="{ onChangeAsync: someValidator }"
  #age="field"
>
  <!-- ... -->
</ng-container>
<ng-container
  [tanstackField]="form"
  name="age"
  asyncDebounceMs={500}
  [validators]="{ onChangeAsync: someValidator }"
  #age="field"
>
  <!-- ... -->
</ng-container>

这将以 500ms 延迟对每个异步调用进行防抖。您甚至可以在每个验证属性上覆盖此属性:

angular-html
<ng-container
  [tanstackField]="form"
  name="age"
  [validators]="{
    onChangeAsyncDebounceMs: 1500,
    onChangeAsync: someValidator,
    onBlurAsync: otherValidator
  }"
  #age="field"
>
  <!-- ... -->
</ng-container>
<ng-container
  [tanstackField]="form"
  name="age"
  [validators]="{
    onChangeAsyncDebounceMs: 1500,
    onChangeAsync: someValidator,
    onBlurAsync: otherValidator
  }"
  #age="field"
>
  <!-- ... -->
</ng-container>

这将每 1500ms 运行一次 onChangeAsync,而 onBlurAsync 将每 500ms 运行一次。

通过模式库进行验证

虽然函数为您的验证提供了更多的灵活性和自定义,但它们可能有点冗长。为了帮助解决这个问题,有一些库提供基于模式的验证,使简写和类型严格的验证变得更加容易。您还可以为整个表单定义单个模式并将其传递到表单级别,错误将自动传播到字段。

标准模式库

TanStack Form 原生支持所有遵循 Standard Schema 规范 的库,最著名的是:

注意: 确保使用模式库的最新版本,因为较旧的版本可能尚不支持 Standard Schema。

验证不会为您提供转换后的值。有关更多信息,请参阅 提交处理

要使用这些库中的模式,您可以将它们传递给 validators 属性,就像使用自定义函数一样:

angular-ts
import { z } from 'zod'

@Component({
  selector: 'app-root',
  standalone: true,
  imports: [TanStackField],
  template: `
    <ng-container
      [tanstackField]="form"
      name="age"
      [validators]="{
        onChange: z.number().gte(13, '您必须年满 13 岁才能创建账户'),
      }"
      #age="field"
    >
      <!-- ... -->
    </ng-container>
  `,
})
export class AppComponent {
  form = injectForm({
    // ...
   })

  z = z

  // ...
}
import { z } from 'zod'

@Component({
  selector: 'app-root',
  standalone: true,
  imports: [TanStackField],
  template: `
    <ng-container
      [tanstackField]="form"
      name="age"
      [validators]="{
        onChange: z.number().gte(13, '您必须年满 13 岁才能创建账户'),
      }"
      #age="field"
    >
      <!-- ... -->
    </ng-container>
  `,
})
export class AppComponent {
  form = injectForm({
    // ...
   })

  z = z

  // ...
}

表单和字段级别的异步验证也受支持:

angular-ts
@Component({
  selector: 'app-root',
  standalone: true,
  imports: [TanStackField],
  template: `
    <ng-container
      [tanstackField]="form"
      name="age"
      [validators]="{
        onChange: z.number().gte(13, '您必须年满 13 岁才能创建账户'),
        onChangeAsyncDebounceMs: 500,
        onChangeAsync: increaseAge
      }"
      #age="field"
    >
      <!-- ... -->
    </ng-container>
  `,
})
export class AppComponent {
  increaseAge = z.number().refine(
    async (value) => {
      const currentAge = await fetchCurrentAgeOnProfile()
      return value >= currentAge
    },
    {
      message: '您只能增加年龄',
    },
  )

  // ...
}
@Component({
  selector: 'app-root',
  standalone: true,
  imports: [TanStackField],
  template: `
    <ng-container
      [tanstackField]="form"
      name="age"
      [validators]="{
        onChange: z.number().gte(13, '您必须年满 13 岁才能创建账户'),
        onChangeAsyncDebounceMs: 500,
        onChangeAsync: increaseAge
      }"
      #age="field"
    >
      <!-- ... -->
    </ng-container>
  `,
})
export class AppComponent {
  increaseAge = z.number().refine(
    async (value) => {
      const currentAge = await fetchCurrentAgeOnProfile()
      return value >= currentAge
    },
    {
      message: '您只能增加年龄',
    },
  )

  // ...
}

如果您需要对 Standard Schema 验证进行更多控制,您可以将 Standard Schema 与回调函数结合使用,如下所示:

angular-ts
@Component({
  selector: 'app-root',
  standalone: true,
  imports: [TanStackField],
  template: `
    <ng-container
      [tanstackField]="form"
      name="age"
      [validators]="{ onChangeAsync: ageValidator }"
      #age="field"
    >
      <!-- ... -->
    </ng-container>
  `,
})
export class AppComponent {
  ageValidator: FieldValidateAsyncFn<any, string, number> = async ({
    value,
    fieldApi,
  }) => {
    const errors = fieldApi.parseValueWithSchema(
      z.number().gte(13, '您必须年满 13 岁才能创建账户'),
    )
    if (errors) return errors

    // 继续您的验证
  }

  // ...
}
@Component({
  selector: 'app-root',
  standalone: true,
  imports: [TanStackField],
  template: `
    <ng-container
      [tanstackField]="form"
      name="age"
      [validators]="{ onChangeAsync: ageValidator }"
      #age="field"
    >
      <!-- ... -->
    </ng-container>
  `,
})
export class AppComponent {
  ageValidator: FieldValidateAsyncFn<any, string, number> = async ({
    value,
    fieldApi,
  }) => {
    const errors = fieldApi.parseValueWithSchema(
      z.number().gte(13, '您必须年满 13 岁才能创建账户'),
    )
    if (errors) return errors

    // 继续您的验证
  }

  // ...
}

防止无效表单被提交

当提交表单时,onChangeonBlur 等回调也会运行,如果表单无效,提交将被阻止。

表单状态对象有一个 canSubmit 标志,当任何字段无效且表单已被触摸时,该标志为 false(canSubmit 在表单被触摸之前为 true,即使某些字段根据其 onChange/onBlur 属性在"技术上"无效)。

您可以通过 injectStore 订阅它并使用该值,例如,在表单无效时禁用提交按钮(在实践中,禁用的按钮不可访问,请改用 aria-disabled)。

angular-ts
@Component({
  selector: 'app-root',
  standalone: true,
  imports: [TanStackField],
  template: `
    <!-- ... -->
    <button type="submit" [disabled]="!canSubmit()">
      {{ isSubmitting() ? '...' : '提交' }}
    </button>
  `,
})
export class AppComponent {
  canSubmit = injectStore(this.form, (state) => state.canSubmit)
  isSubmitting = injectStore(this.form, (state) => state.isSubmitting)

  // ...
}
@Component({
  selector: 'app-root',
  standalone: true,
  imports: [TanStackField],
  template: `
    <!-- ... -->
    <button type="submit" [disabled]="!canSubmit()">
      {{ isSubmitting() ? '...' : '提交' }}
    </button>
  `,
})
export class AppComponent {
  canSubmit = injectStore(this.form, (state) => state.canSubmit)
  isSubmitting = injectStore(this.form, (state) => state.isSubmitting)

  // ...
}