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如何在初始加载后调用角度窗体生成器值更改

ionic3 angular

0

rhysclay · 技术社区 · 7 年前

this.profileFormStageOne.get('nationality').valueChanges.subscribe(val => {
      if (val && val === 'Other') {
        let alert = this.alertCtrl.create({
          title: 'Your Nationality',
          inputs: [
            {
              name: 'nationality',
              placeholder: 'Your Nationality e.g. Brazilian',
            },
          ],
          buttons: [
            {
              text: 'Update Nationality',
              handler: data => {
                this.manualNationality = data.nationality;
                console.log(this.manualNationality);
              },
            },
          ],
        });
        alert.present();
      }
    });

不过,我也使用ngOnChanges()来修补以下形式的值:

  /**
   * Get initial form values
   * Needs to run from ngOnChanges because User in an input & is not ready in constructor
   */
  ngOnChanges() {
    if (this.User) {
      const profile: Profile = this.User.profile;

      this.profileFormStageOne.patchValue({
        nationality: profile.nationality,

问题是,如果国籍字段已设置为“其他”,则在初始呈现(在修补程序值期间)上调用此函数。

2 回复 | 直到 7 年前

1

0

Pavan Bahuguni 7 年前

你可以订阅这样的国籍变更

     this
      .profileFormStageOne.controls['nationality'].valueChanges.subscribe(()=> {
   // your login
 })

2

0

xkeshav 7 年前

get nationality() {
       this.profileFormStageOne.get('nationality');
 }

 this.nationalityChange = this.nationality.valueChanges.subscribe((value: string) => {
            if (value === 'other') {
              // do your requirement
            }
            this.nationality.updateValueAndValidity();
        });

pathValue() 方法设置默认值 ngAfterViewInit() 钩子

ngOnDestroy() {
        this.nationalityChange.unsubscribe();
    }