如何以编程方式设置Angular 2表单控件值？

Question

How do I change an Angular 2 control from code?

When I do it like this:

control.value = "new value";

I get the following error:

TypeError: Cannot set property value of #<AbstractControl> which has only a getter

Answer 1

You can use the updateValue method:

control.updateValue("new value");

update:

You can now use setValue :

control.setValue("new value");

Answer 2

在访问updateValue方法之前，您需要将AbstractControl转换为Control ：

(<Control>yourControl).updateValue(val);

Answer 3

You need to use both updateValue and updateValueAndValidity to update the value of a control and also trigger validators / calculate state.

Here is a sample:

control.updateValue("new value");
control.updateValueAndValidity();

Answer 4

In the final version of Angular 2, the .changeValue(newValue: string) method was removed and exchanged for .patchValue(newValue: string)

so you can do control.patchValue('your new value goes here');