angular 实现同步验证器跨字段验证的方法

export const identityRevealedValidator: ValidatorFn = (control: FormGroup): ValidationErrors | null => {
 const name = control.get('name');
 const alterEgo = control.get('alterEgo');

 return name && alterEgo && name.value === alterEgo.value ? { 'identityRevealed': true } : null;
};

  // 判断总占比是否等于100
  export const scoreWeightSumValidator: ValidatorFn = (formGroup: FormGroup): ValidationErrors | null => {
  const sumLegal = formGroup.get('finalScoreWeight')
    .value + formGroup.get('middleScoreWeight')
    .value + formGroup.get('usualScoreWeight')
    .value === 100;
    // 如果是，返回一个 null，否则返回 ValidationErrors 对象。
  return sumLegal ? null : {'scoreWeightSum': true};
};

  ngOnInit(): void {
  this.scoreSettingAddFrom = this.fb.group({
    finalScoreWeight: [null, [Validators.required, scoreWeightValidator]],
    fullScore: [null, [Validators.required]],
    middleScoreWeight: [null, [Validators.required, scoreWeightValidator]],
    name: [null, [Validators.required]],
    passScore: [null, [Validators.required]],
    priority: [null, [Validators.required]],
    usualScoreWeight: [null, [Validators.required, scoreWeightValidator]],
  }, {validators: scoreWeightSumValidator});
}

  <nz-form-item nz-row>
  <nz-form-control nzValidateStatus="error" nzSpan="12" nzOffset="6">
    <nz-form-explain
      *ngIf="scoreSettingAddFrom.errors?.scoreWeightSum &&
       scoreSettingAddFrom.get('middleScoreWeight').dirty &&
       scoreSettingAddFrom.get('finalScoreWeight').dirty &&
       scoreSettingAddFrom.get('usualScoreWeight').dirty">成绩总占比需等于100%!
    </nz-form-explain>
  </nz-form-control>
</nz-form-item>