带有ngModel的动态角度复选框 [英] angular mat-checkbox dynamically with ngModel

问题描述

我有一个要约类，它具有一个属性单位"作为对象数组.

I have a class Offer which have one property "units" as array of objects.

export class Offer {
   public propertyA: string;
   public propertyB: string;
   public units: Unit[];
}

export class Unit {    
    public code: string,
    public name: string,
    public checked: boolean
}

我正在使用Angular2，这些单位必须是用户可以选择的复选框. 我也在用角形材料.

I am using Angular2, these units must be checkboxes the user can select. Also I am using angular material.

html代码如下:

<div *ngFor="let unit of model.units; let i=index">
  <mat-checkbox [(ngModel)]="model.units[i].checked"
    id="units[{{i}}]" name="units[{{i}}]">
       {{ unit.name }}
  </mat-checkbox>                        
</div>    

units属性使用以下方式加载:

The units property is loaded using:

this.model.units.push(new Unit("code1","name1", false));
this.model.units.push(new Unit("code2","name2", false));
this.model.units.push(new Unit("code3","name3", false));

我发送表单时，选中的属性不包含选中的值.

When I send the form the checked property does not contains the checked value.

我在做什么错??

推荐答案

添加[checked]="unit.checked"并从mat-checkbox中删除ngModel，id和name.加载页面时，这会执行一种单向绑定，但是要使两种方式绑定工作，您需要做类似的事情，就像我在我的项目中所做的那样:

Add [checked]="unit.checked" and remove ngModel, id and name from your mat-checkbox. This does one way binding when you load the page but to make the two way binding work you need to do something similar like this which i have done in my project:

在更改时通过$event并手动在组件文件中设置值:

Pass the $event on change and set the value in the component file manually:

将HTML更改为:

<div *ngFor="let unit of model.units">
  <mat-checkbox [checked]="unit.checked" 
  (change)="valueChange(model.units,unit,$event)">
       {{ unit.name }}
  </mat-checkbox>                        
</div>

将此添加到组件文件:

valueChange(model.units, unit, $event) {
        //set the two-way binding here for the specific unit with the event
        model.units[unit].checked = $event.checked;
    }

编辑/更新:最近找到了一种无需明确处理的双向绑定解决方案

EDIT/UPDATE: Found a solution recently for two way binding without handling it explicitly

确保model.units具有checked的属性.这是添加它的最简单方法:

Make sure model.units have a property for checked. This is the easiest way to add it:

component.ts:

component.ts:

this.model.units.forEach(item => {
                       item.checked = false; //change as per your requirement
                    });

html:

 <div *ngFor="let unit of model.units;let i=index">
    <mat-checkbox [(ngModel)]="unit.checked" [checked]="unit.checked"                                                                                    
    name="{{i}}-name">  //make sure name is unique for every item                             
    </mat-checkbox>
</div>

如果您还想控制启用/禁用选项，请尝试添加以下内容:

If you want to control the enable/disable options as well try adding this:

component.ts:

component.ts:

this.model.units.forEach(item => {
                       item.checked = false;//change as per your requirement
                       item.disabled = true;//change as per your requirement
                        });

html:

<div *ngFor="let unit of model.units;leti=index">
        <mat-checkbox [(ngModel)]="unit.checked" [checked]="unit.checked"
         [disabled]="unit.disabled"                                                                                    
       name="{{i}}-name">//make sure name is unique for every item
        </mat-checkbox>
    </div>

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