第一个建议的解决方案是有效的，我们只需要改变

selBox.value = val;

To

selBox.innerText = val;

也就是说,

HTML:

<button (click)="copyMessage('This goes to Clipboard')" value="click to copy" >Copy this</button>

.ts文件:

copyMessage(val: string){
    const selBox = document.createElement('textarea');
    selBox.style.position = 'fixed';
    selBox.style.left = '0';
    selBox.style.top = '0';
    selBox.style.opacity = '0';
    selBox.innerText = val;
    document.body.appendChild(selBox);
    selBox.focus();
    selBox.select();
    document.execCommand('copy');
    document.body.removeChild(selBox);
  }

以下方法可用于复制消息:-

export function copyTextAreaToClipBoard(message: string) {
  const cleanText = message.replace(/<\/?[^>]+(>|$)/g, '');
  const x = document.createElement('TEXTAREA') as HTMLTextAreaElement;
  x.value = cleanText;
  document.body.appendChild(x);
  x.select();
  document.execCommand('copy');
  document.body.removeChild(x);
}

修改版本的jockeisorby的回答，修复事件处理程序没有被正确删除。

copyToClipboard(item): void {
    let listener = (e: ClipboardEvent) => {
        e.clipboardData.setData('text/plain', (item));
        e.preventDefault();
    };

    document.addEventListener('copy', listener);
    document.execCommand('copy');
    document.removeEventListener('copy', listener);
}

你可以使用Angular模块来实现:

navigator.clipboard.writeText('your text').then().catch(e => console.error(e));

第一个建议的解决方案是有效的，我们只需要改变

selBox.value = val;

To

selBox.innerText = val;

也就是说,

HTML:

<button (click)="copyMessage('This goes to Clipboard')" value="click to copy" >Copy this</button>

.ts文件:

copyMessage(val: string){
    const selBox = document.createElement('textarea');
    selBox.style.position = 'fixed';
    selBox.style.left = '0';
    selBox.style.top = '0';
    selBox.style.opacity = '0';
    selBox.innerText = val;
    document.body.appendChild(selBox);
    selBox.focus();
    selBox.select();
    document.execCommand('copy');
    document.body.removeChild(selBox);
  }

用纯Angular和ViewChild为自己找到了最简单的解决方案。

import { Component, ViewChild } from '@angular/core';

@Component({
  selector: 'cbtest',
  template: `
    <input type="text" #inp/>
    <input type="button" (click)="copy ()" value="copy now"/>`
})

export class CbTestComponent
{
  @ViewChild ("inp") inp : any;

  copy ()
  {
    // this.inp.nativeElement.value = "blabla";  // you can set a value manually too

    this.inp.nativeElement.select ();   // select
    document.execCommand ("copy");      // copy
    this.inp.nativeElement.blur ();     // unselect
  }
}