Angular 角度/如何将获取的数据从字符串转换为数组

我在对话框中编辑了表单，但我正在接收的select的api数据是字符串而不是数组，因此我得到以下错误：

错误：值必须是多选模式下的数组。

campaign.ts

  ngOnInit(): void {
    this.fetchdata();
  }

  fetchdata() {
    this.campaignService.sendGetRequest()
    .subscribe((data: any[])=>{
      this.campaigns = data;
    })
  }

  onEdit(item){
    this.campaigns.findIndex(i => i.id == item.id);
    const dialogRef = this.dialog.open(EditComponent,{
          data: item
        });
  }

this.editForm = this.fb.group({
  Name: this.data.name,
  SmsText: [this.data.smsText,  [Validators.required]],
  SmsSendDate: [this.data.smsSendDate,  [Validators.required]],
  SmsSendHoursRange: this.fb.group({
    start: [this.data.smsSendHoursRange.start,  [Validators.required]],
    end: [this.data.smsSendHoursRange.end,  [Validators.required]],
  }),
  Branch: [this.data.branch],
  InspectionResult: [this.data.inspectionResult],
  Categories: [this.data.categories],
  DateOfIssue: [this.data.dateOfIssue],
  Brand: [this.data.brand],
  VehicleCategory: [this.data.vehicleCategory],
  OwnerStatus: [this.data.ownerStatus],
  IsPhys: [this.data.isPhys],
  IsJRDC: [this.data.isJRDC]
});

// get centers
this.campaignService.getCenters().subscribe((data: any[])=>{
  this.centers = data;
})
// get vehicles
this.campaignService.getCategories().subscribe((data: any[])=>{
  this.categories = data;
})

编辑.ts

  ngOnInit(): void {
    this.fetchdata();
  }

  fetchdata() {
    this.campaignService.sendGetRequest()
    .subscribe((data: any[])=>{
      this.campaigns = data;
    })
  }

  onEdit(item){
    this.campaigns.findIndex(i => i.id == item.id);
    const dialogRef = this.dialog.open(EditComponent,{
          data: item
        });
  }

this.editForm = this.fb.group({
  Name: this.data.name,
  SmsText: [this.data.smsText,  [Validators.required]],
  SmsSendDate: [this.data.smsSendDate,  [Validators.required]],
  SmsSendHoursRange: this.fb.group({
    start: [this.data.smsSendHoursRange.start,  [Validators.required]],
    end: [this.data.smsSendHoursRange.end,  [Validators.required]],
  }),
  Branch: [this.data.branch],
  InspectionResult: [this.data.inspectionResult],
  Categories: [this.data.categories],
  DateOfIssue: [this.data.dateOfIssue],
  Brand: [this.data.brand],
  VehicleCategory: [this.data.vehicleCategory],
  OwnerStatus: [this.data.ownerStatus],
  IsPhys: [this.data.isPhys],
  IsJRDC: [this.data.isJRDC]
});

// get centers
this.campaignService.getCenters().subscribe((data: any[])=>{
  this.centers = data;
})
// get vehicles
this.campaignService.getCategories().subscribe((data: any[])=>{
  this.categories = data;
})

edit.html

  <div class="column">
    <mat-form-field appearance="fill">
      <mat-label>Car category</mat-label>
      <mat-select multiple formControlName="Categories">
        <mat-option *ngFor="let item of categories" [value]="item.id">{{item.description}}</mat-option>
      </mat-select>
    </mat-form-field>
  </div>
<div class="columns">
  <mat-form-field appearance="fill">
    <mat-label>Centers</mat-label>
    <mat-select multiple formControlName="Branch">
      <mat-option *ngFor="let item of centers" [value]="item.centerCode">{{item.address}}</mat-option>
    </mat-select>
  </mat-form-field>
</div>

忽略不匹配的行（无声失败）

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忽略不匹配的行（无声失败）

在javascript中有一个函数split（separator），它通过分隔符将字符串拆分为数组

因此，在您的情况下，当您构建formGroup时，您将设置，例如：

---

Branch:[this.data.Branch.split（'，'）]，

在javascript中有一个函数split（separator），它通过分隔符将字符串拆分成数组

因此，在您的情况下，当您构建formGroup时，您将设置，例如：

---

Branch:[this.data.Branch.split（“，”）]，

嘿，谢谢你的回答，很有效！还有一个问题，有时某些数据将为空，因此我会遇到以下错误：无法读取nullQuick解决方案的属性“split”：（this.data.branch | |“”）。split（'，'））或更长，并且仅处理会使this.data.branch为空！==无效的this.data.branch.split（'，'）：[]谢谢！！！！！！嘿，谢谢你的回答，很有效！还有一个问题，有时某些数据将为空，因此我会遇到以下错误：无法读取nullQuick解决方案的属性“split”：（this.data.branch | |“”）。split（'，'））或更长，并且仅处理会使this.data.branch为空！==无效的this.data.branch.split（'，'）：[]谢谢！！！！！！