typescript Angular 6 - textarea (change) 永远不会改变 textarea 的内容

Angular 6 - textarea (change) ever doesn't change the contents of the textarea

提问by ConnorsFan

I am having an isse with a textarea where if I modify the contents on the textarea and the (change) is trigger it won't change the contents of the textarea by code.

我有一个 textarea 问题，如果我修改 textarea 上的内容并且（更改）被触发，它不会通过代码更改 textarea 的内容。

Here is an example:

下面是一个例子：

app.component.html

应用程序组件.html

<textarea #content (change)="dosomething(content.value)">{{ thecontents | json }}</textarea>

app.component.ts

app.component.ts

thecontents;

内容;

dosomething(data) {

    // this will overwrite whatever is already in the textarea
    this.thecontents = {  something : 'someother'};
}

For some reason the textarea is not being changed when the (change)is triggered

由于某种原因，文本区域在(change)触发时没有改变

Why? How can I fix this?

为什么？我怎样才能解决这个问题？

采纳答案by Chellappan ?

If you don't want to ngModel you can use View Child Directive to achive the same result

如果您不想使用 ngModel，您可以使用 View Child Directive 来获得相同的结果

@ViewChild('content') con:ElementRef;
  thecontents={something:''};
name='';
  dosomething(data) {

    // this will overwrite whatever is already in the textarea

this.con.nativeElement.value=1;

}

I have edited your code check this out https://stackblitz.com/edit/angular-xjksed

我已经编辑了您的代码，请查看https://stackblitz.com/edit/angular-xjksed

回答by ConnorsFan

Bind the content of the textarea with [value]or with [ngModel]:

用[value]或绑定 textarea 的内容[ngModel]：

<textarea (change)="dosomething($event.target.value)" [value]="thecontents | json"></textarea>

<textarea (change)="dosomething($event.target.value)" [ngModel]="thecontents | json"></textarea>

See this stackblitzfor a demo.

有关演示，请参阅此 stackblitz。