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Property 'value' does not exist on type EventTarget in TypeScript [duplicate]

This question already has answers here: Property 'value' does not exist on type 'EventTarget' (16 answers) Closed 17 days ago.

So the following code is in Angular 4 and I can't figure out why it doesn't work the way as expected.

Here is a snippet of my handler:

onUpdatingServerName(event: Event) {
  console.log(event);
  this.newserverName = event.target.value; //this wont work
}

HTML element:

<input type="text" class="form-control" (input)="onUpdatingServerName($event)">

The code gives me the error:

Property 'value' does not exist on type 'EventTarget'.

But as it can be seen in the console.log that value does exist on the event.target.

we can use (e.target as HTMLInputElement).value
Bro, I struggled with this for hours, you simply have to remove the type from the method. onUpdatingServerName(event);

r
rofrol

event.target here is an HTMLElement which is the parent of all HTML elements, but isn't guaranteed to have the property value. TypeScript detects this and throws the error. Cast event.target to the appropriate HTML element to ensure it is HTMLInputElement which does have a value property:

(event.target as HTMLInputElement).value

Per the documentation:

Type the $event The example above casts the $event as an any type. That simplifies the code at a cost. There is no type information that could reveal properties of the event object and prevent silly mistakes. [...] The $event is now a specific KeyboardEvent. Not all elements have a value property so it casts target to an input element.

(Emphasis mine)


A bit cleaner syntax var element = ev.target as HTMLElement
For me, HTMLInputElement worked instead of HTMLElement as HTMLElement does not have value in the interface.
The best approach, in my opinion, is having onFieldUpdate(event: { target: HTMLInputElement }) { in the called function. See my answer below.
For Angular 9 use "as" syntax. event.target as HtmlInputlement
@Prescol You have a typo. It's event.target as HTMLInputElement
M
Mikael Lirbank

Passing HTMLInputElement as a generic to the event type should work too:

onUpdatingServerName(event: React.ChangeEvent<HTMLInputElement>) {
  console.log(event);
  this.newserverName = event.target.value;
}

This is better than type assertions.
This will not work if the function is called from i.e. an onChange proeperty handler reference in React code though. The react handler does not expect the type to be set for the React.ChangeEvent and will show a typing error. I had to revert to (a variant of) the selected answer instead, with a cast: (event.target as HTMLInputElement).value.
This seemed to work for me fine in a React component. Maybe it's the version of React? We're currently on 16.8.*.
M
Matt S.

Here's another fix that works for me:

(event.target as HTMLInputElement).value

That should get rid of the error by letting TS know that event.target is an HTMLInputElement, which inherently has a value. Before specifying, TS likely only knew that event alone was an HTMLInputElement, thus according to TS the keyed-in target was some randomly mapped value that could be anything.


This was really helpful in React where it tried to interpret as JSX.
B
Beau Smith

I was looking for a solution to a similar TypeScript error with React:

Property 'dataset' does not exist on type EventTarget in TypeScript

I wanted to get to event.target.dataset of a clicked button element in React:

<button
  onClick={onClickHandler}
  data-index="4"
  data-name="Foo Bar"
>
  Delete Candidate
</button>

Here is how I was able to get the dataset value to "exist" via TypeScript:

const onClickHandler = (event: React.MouseEvent<HTMLButtonElement>) => {
  const { name, index } = (event.target as HTMLButtonElement).dataset
  console.log({ name, index })
  // do stuff with name and index…
}

Question is tagged as Angular so a React answer seems off topic.
Regardless… it has multiple up votes, thus this answer has been helpful to others.
Works like a charm. onChange={(event: ChangeEvent<HTMLInputElement>): void => { setTextFilter(event.target.value); }}
K
Koustav

In template -

`(keyup)="value2=$any($event.target).value"`

in component -

getInput(event: Event) {
  this.value1 = (event.target as HTMLInputElement).value;
}

This is the most elegant solution yet.
b
belvederef

The way I do it is the following (better than type assertion imho):

onFieldUpdate(event: { target: HTMLInputElement }) {
  this.$emit('onFieldUpdate', event.target.value);
}

This assumes you are only interested in the target property, which is the most common case. If you need to access the other properties of event, a more comprehensive solution involves using the & type intersection operator:

event: Event & { target: HTMLInputElement }

This is a Vue.js version but the concept applies to all frameworks. Obviously you can go more specific and instead of using a general HTMLInputElement you can use e.g. HTMLTextAreaElement for textareas.


K
Kartik Chandra

This works for me in ANGULAR HTML Component !!

$any($event.target).value

Source Link: https://www.tektutorialshub.com/angular/property-value-does-not-exist-on-type-eventtarget-error-in-angular/


working well. Thanks for the answer.
J
JillAndMe

You should use event.target.value prop with onChange handler if not you could see :

index.js:1437 Warning: Failed prop type: You provided a `value` prop to a form field without an `onChange` handler. This will render a read-only field. If the field should be mutable use `defaultValue`. Otherwise, set either `onChange` or `readOnly`.

Or If you want to use other handler than onChange, use event.currentTarget.value


this works for me but i am not sure using event.currentTarget.value is the best approach.
F
Faizan Ahmad

To solve this problem, use the $any typecast function ($any($event.target).value) to stop the type checking in the template.

Read more here.


This one works for me on angular v14
s
shahidfoy

you can also create your own interface as well.

    export interface UserEvent {
      target: HTMLInputElement;
    }

       ...

    onUpdatingServerName(event: UserEvent) {
      .....
    }

A
Amit Baderia

You can explicitly parse it into "HTMLInputElement" and then access 'value'

onUpdatingServerName(event: Event) {
  console.log(event);
  this.newserverName = (<HTMLInputElement>event.target).value; 
}

C
Codemaker

As you know, TypeScript has been always strictly on the element data type. So, You can't directly access attributes of an element without specifying its data type. The event.target is an HTMLElement which is the parent of all HTML elements, but isn't guaranteed to have the property value.

So, we need to typecast the variable event.target then only we can access the value attribute from it.

OnUpdatingServerName (event: Event) {
  console.log(event);
  var element = event.target as HTMLElement
  this.newserverName = element.value;
}

I
Igor Sukharev

I would recommend creating a utility type:

interface MyEvent<T extends EventTarget> extends Omit<Event, 'target'> {
  target: T;
}

And then use it like this:

function onChange({ target: { value } }: MyEvent<HTMLInputElement>) => {
  doSomethingWith(value);
}

V
Vadim Ovchinnikov

Declare interface

export interface HTMLInputEvent extends Event {
  target: HTMLInputElement & EventTarget;
}

which can be re-used as a type for different input events

public onChange(event: HTMLInputEvent) {
  const value = event.target.value;
}

A
Azhar Uddin Sheikh

React has some interface like ChangeEvent for onChange, FormEvent for onSubmit etc

I was also trying to do similar like this below solution worked for me

handleChange (e : React.ChangeEvent<HTMLInputElement>) {
  console.log(e.currentTarget.value);
}


<input 
   autoFocus
   value={this.state.account.username}
   onChange={this.handleChange}
   id="username" 
   type="text" 
   className="form-control" 
/>

A
Alok Kumar Sahoo

Please try this one

<input type = 'text' [value] = 'value' (input) = 'data = $any($event.target).value'>

p
piotrek1543

Try code below:

  console.log(event['target'].value)

it works for me :-)


better remove your answer
d
dylanroman03

add any type to event

event: any

example

[element].addEvenListener('mousemove', (event: any) =>{
//CODE//
} )

what happens is that typescript adds "event" (click in this case) as Event type and for some reason it doesn't recognize some properties. Adding it of type any no longer exists this problem, this works for any document.[Property]


Welcome on the SO! Why and how? Please explain.
you may remove your answer if it get minused hardly
By adding any will give warning on compile-time, and not recommended to use any in TS file, otherwise the purpose of using ts file is dying.
@ZeeshanSafdar I agree that you shouldn't do what @dylanroman03 has done here, however any is perfectly fine to use in cases where the object can in fact be anything. In general, if you know what the object's properties are (like we do here), you shouldn't be using any. If the object can have any properties, you should use any.