如何在模板中以角色形式访问动态的输入名称属性

Question

我将 ngx-datatable包装在form> form标签中，以便在表单元格中验证inputs。由于如何填充表的性质，我设置了输入name属性，属性属性正常

<form #tableForm="ngForm">
  <ngx-datatable
    [rows]="_rows">
        <ng-container *ngFor="let column of rowDeffinition; let columnIndex=index">
          <ngx-datatable-column [prop]="column.key" [name]="column.label">
            <ng-template ngx-datatable-cell-template let-rowIndex="rowIndex" let-value="value" let-row="row">
              <input
                class="cell-input"
                (blur)="updateCellValue($event, column.key, rowIndex)"
                type="text"
                [ngModel]="value"
                [name]="rowIndex + '-' + column.key"
              />

              ...

            </ng-template>
          </ngx-datatable-column>
        </ng-container>
  </ngx-datatable>
</form>

，name属性将在模板中创建局部变量，您可以访问输入通过变量名称控制属性。

<input type="text" name="name" [(ngModel)]="name" required minlength="4" />
<div *ngIf="name.invalid && name.touched">

我想知道如何以相同的方式动态执行此操作。到目前为止，我能够通过表格参考访问输入控件

<span *ngIf="!tableForm.controls[rowIndex + '-' + column.key]?.valid && 
      !tableForm.controls[rowIndex + '-' + column.key]?.pristine"
      class="[ c-validation-message ]">
  required
</span>

Answer 1

您可以将输入包装到新组件中，并且可以通过@viewchildren（...）访问这些生成的组件 in Parent Components .ts file> File：

@ViewChildren(NgxDatatableInput) datatableInputs: QueryList<NgxDatatableInput>;

我建议在中创建方法父组件，从datatableInputs by name作为参数中检索混凝土datatableInput。之后，您可以在生成的，新的验证pancomponent中使用此方法：

<ValidationSpan [control]="getDatatableInput(dynamicName)">
</ValidationSpan>

verialationspancomponent的模板：

<span *ngIf="!control.valid && 
      !control.pristine"
      class="[ c-validation-message ]">
  required
</span>

Answer 2

灵感来自这个答案我想出了以下解决方案

<form #tableForm="ngForm">
  <ngx-datatable
    [rows]="_rows">
        <ng-container *ngFor="let column of rowDeffinition; let columnIndex=index">
          <ngx-datatable-column [prop]="column.key" [name]="column.label">
            <ng-template ngx-datatable-cell-template let-rowIndex="rowIndex" let-value="value" let-row="row">
              <!-- Helper template allowing to define few variables for more readable property binding-->
              <ng-template #cellContent [ngTemplateOutlet]="cellContent"              
                let-cellName="cellName" let-isValidInput="isValidInput" let-isPristineInput="isPristineInput"
                let-isRequiredInput="isRequiredInput"
                [ngTemplateOutletContext]="{
                  cellName: rowIndex + '-' + column.key,
                  isValidInput: tableForm.controls[rowIndex + '-' + column.key]?.valid,
                  isPristineInput: tableForm.controls[rowIndex + '-' + column.key]?.pristine,
                  isRequiredInput: column.input?.required
                }">

                <input
                  class="cell-input"
                  (blur)="updateCellValue($event, column.key, rowIndex)"
                  type="text"
                  [ngModel]="value"
                  [name]="cellname"
                />

                ...

              </ng-template>
            </ng-template>
          </ngx-datatable-column>
        </ng-container>
  </ngx-datatable>
</form>

，这可以极大地提高一般的可读性，因为我的表具有非常复杂的逻辑，很复杂，我在类似结构中跟踪单元格的状态：

interface EditTableRowStatus {
    editing: { [columnId: string]: boolean},
    changed: { [columnId: string]: boolean},
    addedRow: boolean;
  }

let rowsStates = EditTableRowStatus[]

这导致模板中的超级复杂属性绑定

<input
  class="cell-input"
  *ngIf="column.input?.type === INPUT_TYPES.TEXT && (rowsStates[rowIndex]?.editing?.[column.key] || rowsStates[rowIndex]?.addedRow)"
  [autofocus]="!rowsStates[rowIndex]?.addedRow || columnIndex === 0 "
  (blur)="updateCellValue($event, column.key, rowIndex)"
  type="text"
  [ngModel]="value"
  [ngClass]="{'has-changes': rowsStates[rowIndex]?.changed?.[column.key]}"
  [name]="rowIndex + '-' + column.key"
  [required]="column.input?.required"
/>

到现在变得更加可读性

<input
  class="cell-input"
  *ngIf="inputType === INPUT_TYPES.TEXT && (isEditing || isAddedRow)"
  [autofocus]="!isAddedRow || columnIndex === 0 "
  (blur)="updateCellValue($event, column.key, rowIndex)"
  type="text"
  [ngModel]="value"
  [ngClass]="{'has-changes': isChanged}"
  [name]="cellName"
  [required]="isRequiredInput"
/>