javascript - 如何在Angular 2中添加条件属性？(How to add conditional attribute in Angular 2?)

Question

How can I conditionally add an element attribute eg the checked of a checkbox?

(我如何能有条件地添加元素属性，例如checked复选框的？)

Previous versions of Angular had NgAttr and I think NgChecked which all seem to provide the functionality that I'm after.

(以前的Angular版本具有NgAttr ，我认为NgChecked似乎都提供了我所追求的功能。)

However, these attributes do not appear to exist in Angular 2 and I see no other way of providing this functionality.

(但是，这些属性在Angular 2中似乎不存在，我看不到提供此功能的其他方法。)

  ask by Jonathan Miles translate from so

Answer 1

null removes it:

(null将其删除：)

[attr.checked]="value ? '' : null"

or

(要么)

[attr.checked]="value ? 'checked' : null"