点击复制指定内容

项目为angualr4

1.在HTML中加一个input，（不可display:none）

 ```

<input type="text" name="copyInput" id="copyInput" [(ngModel)]="copyvalue"

style="position: absolute;left:-100px;bottom:-100px">

```

2.js代码

```

import { ElementRef } from '@angular/core';

 

public copyvalue = '';

 

public toCopy(item) {

const input = this.el.nativeElement.querySelector('#copyInput');

this.copyvalue = item.url;

input.value = item.url;

input.select();

document.execCommand('Copy');

this._message.success('复制成功');

}

 

constructor(

private el: ElementRef

) {}

```

(getElementByClassName 无效)