Question

我有这种形式，如果我将其保留为空或无效，则会在每个字段下显示错误消息。

<form #projectForm="ngForm" (ngSubmit)="onSubmit()">

     <div class="form-group col-md-6" [class.has-error]="codeControl.invalid && codeControl.touched">
        <label  class="control-label">code</label>
        <input type="text" class="form-control" required [(ngModel)]="projet.code" id="code" name="code" #codeControl="ngModel">
        <span class="help-block" *ngIf="codeControl.invalid && codeControl.touched">code is required </span>
      </div>



      <div class="form-group col-md-6" [class.has-error]="libelleControl.invalid && libelleControl.touched">
        <label class="control-label">libelle</label>
        <input type="text" class="form-control" required [(ngModel)]="projet.libelle" id="libelle" name="libelle" #libelleControl="ngModel">
      <span class="help-block" *ngIf="libelleControl.invalid && libelleControl.touched"> libelle is required </span>
      </div>


    <button type="submit" class="btn btn-primary" >submit </button>

    
  </form>

但是，当涉及到提交按钮时，我不希望在表单有效之前禁用提交按钮，而是希望提交按钮边框变为红色，并且在以下情况下在提交按钮下方显示红色错误消息：单击，表格无效。我该如何实现？

Answer 1

我将使用简单的getter来管理“提交btn”的状态

get isFormValid():boolean {
  this.ngForm && this.ngForm.valid;
}

然后

 <button type="submit" class="btn btn-primary" [class.cssClassToManageBtnState]="isFormValid" >submit </button>

Answer 2

尝试：在您的组件上

success: any;

constructor () 
{
this.success = true;
}

onSubmit(){

if(this.yourform.invalid){
    this.success= false; 
    return;
}

}

在您的html上

 <div *ngIf="success;then content else other_content"></div>    
  <ng-template #content>
    <button type="submit" class="btn btn-primary" >submit </button>
  </ng-template>

  <ng-template #other_content>
  <button type="submit" class="btn btn-primary" style="border: 2px solid red">submit 
  </button>
   <!-- your error message goes here -->
 </ng-template>

我在How to use *ngIf else?的此处复制了* ngIf

Answer 3

我们必须覆盖“提交”按钮的默认行为。因此，删除按钮类型为Submit并向其中添加click事件

  <button type="button" (click)="onSubmit()" class="btn btn-primary" >submit </button>

删除表单标签中的Submit事件

<form #projectForm="ngForm">

将条件类添加到按钮

<button type="submit" (click)="onSubmit()" class="btn btn-primary" [ngClass]="projectForm.valid ? '' : 'invalid-form-btn'" >submit </button>
<span *ngIf="!projectForm.valid">The form is not valid </span>

.invalid-form-btn {
    border: 1px solid red; 
}

角度-表单无效时在提交时显示错误消息

3 个答案: