如何检查ngModel输入字段是否脏? [英] How to check an ngModel input field is dirty?

问题描述

我有这个HTML模板:

I have this HTML template:

<input type="text"
  ngModel
  #myValue="ngModel"
  name="{{ fieldName }}"
  id="{{ fieldName }}"
  value="{{ myVal }}"
  class="form-control"
  (change)="checkDirty(myValue)">

如何检查my.component.ts文件中的该字段是否脏?

How do I check this field is dirty in my.component.ts file?

现在，我的my.component.ts文件中只有以下基本代码:

Now I have only this basic code in my.component.ts file:

export class UriFieldComponent implements OnInit {
    constructor() { }

    ngOnInit() { }

    checkDirty(value) {
        // in here I need to check is dirty or not
    }
}

推荐答案

NgModel类具有脏属性.这意味着您可以:

NgModel class has an dirty property in it. This mean you can do:

checkDirty(value) {
    if (value.dirty) {
      ...
    }
}

但是，您使用它的方式是不正确的，如果您在输入更改时检查了dirty属性，则很明显该输入是肮脏的！.换句话说，如果您要使用 checkDirty 函数，则输入总是脏的.

But, the way you use it is incorrect, if you check the dirty property on input change it is obvious that the input is dirty!. In other words, if you're getting to your checkDirty function the input is always dirty.

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