Angular – FormArray中的唯一性验证器

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我创建了一个自定义验证器来验证FormArray中的唯一性.我想在特定(s)值已经在数组中时显示错误.

问题是它没有按预期工作.

实际行为:

重现步骤:

>添加3“输入” – 地址;
>填写输入1;
>使用不同的值填充输入2;
>使用相同的输入值1填充输入3; (输入1和输入3均未出现错误)

预期行为:

如果“X组”中显示相同的值,则其特定输入必须显示错误.

在上述情况下,错误应出现在输入1和3上.

假设我有4个输入:

>值:堆栈
>价值:溢出
>值:堆栈
>价值:溢出

4个输入必须显示错误,因为它们都是重复的.

static uniqueBy = (field: string,caseSensitive = true): ValidatorFn => {
  return (formArray: FormArray): { [key: string]: boolean } => {
    const controls = formArray.controls.filter(formGroup => {
      return isPresent(formGroup.get(field).value);
    });
    const uniqueObj = { uniqueBy: true };
    let found = false;

    if (controls.length > 1) {
      for (let i = 0; i < controls.length; i++) {
        const formGroup = controls[i];
        const mainControl = formGroup.get(field);
        const val = mainControl.value;    
        const mainValue = caseSensitive ? val.toLowerCase() :  val;

        controls.forEach((group,index) => {
          if (i === index) {
            // Same group
            return;
          }

          const currControl = group.get(field);
          const tempValue = currControl.value;
          const currValue = caseSensitive ? tempValue.toLowerCase() : tempValue;
          let newErrors;

          if ( mainValue === currValue) {
            if (isBlank(currControl.errors)) {
              newErrors = uniqueObj;
            } else {
              newErrors = Object.assign(currControl.errors,uniqueObj);
            }

            found = true;
          } else {
            newErrors = currControl.errors;

            if (isPresent(newErrors)) {
              // delete uniqueBy error
              delete newErrors['uniqueBy'];

              if (isBlank(newErrors)) {
                // {} to undefined/null
                newErrors = null;
              }
            }
          }

          // Add specific errors based on condition
          currControl.setErrors(newErrors);
        });
      }

      if (found) {
        // Set errors to whole formArray
        return uniqueObj;
      }
    }

    // Clean errors
    return null;
  };
}

你可以在这里查看DEMO.

在您的代码中使用嵌套for循环,您正在交错错误.

以下是验证状态查找每次迭代的方式:

0      [null,"{"uniqueBy":true}",null]

  1      ["{"uniqueBy":true}",null]

  2      [null,"{}",null]

http://plnkr.co/edit/MTjzQ9KiJHJ56DVAZ155?p=preview(添加三个地址并观察输出)

在下面的代码中,我只在loop语句之前清除错误一次,不再删除错误.

controls.map(formGroup => formGroup.get(field)).forEach(x => x.errors && delete x.errors['uniqueBy']);
for (let i: number = 0; i < controls.length; i++) {
    const formGroup: FormGroup = controls[i] as FormGroup;
    const mainControl: AbstractControl = formGroup.get(field);
    const val: string = mainControl.value;

    const mainValue: string = caseSensitive ? val.toLowerCase() :  val;
    controls.forEach((group: FormGroup,index: number) => {
        if (i === index) {
            return;
        }

        const currControl: any = group.get(field);
        const tempValue: string = currControl.value;
        const currValue: string = caseSensitive ? tempValue.toLowerCase() : tempValue;
        let newErrors: any;

        if ( mainValue === currValue) {
            if (isBlank(currControl.errors)) {
                newErrors = uniqueObj;
            } else {
                newErrors = Object.assign(currControl.errors,uniqueObj);
            }
            currControl.setErrors(newErrors);
            find = true;
        }
    });
}

Plunker Example

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