typescript 입력 onchange event.target.value

typescript 입력 onchange event.target.value

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내 반응 및 타이프 스크립트 앱에서 다음을 사용 onChange={(e) => data.motto = (e.target as any).value}합니다..

클래스의 타이핑을 올바르게 정의하는 방법은 any무엇입니까?

export interface InputProps extends React.HTMLProps<Input> {
...

}

export class Input extends React.Component<InputProps, {}> {
}

내가 넣으면 target: { value: string };:

ERROR in [default] /react-onsenui.d.ts:87:18
Interface 'InputProps' incorrectly extends interface 'HTMLProps<Input>'.
  Types of property 'target' are incompatible.
    Type '{ value: string; }' is not assignable to type 'string'.

---

일반적으로 이벤트 핸들러는를 사용해야합니다 e.currentTarget.value. 예 :

onChange = (e: React.FormEvent<HTMLInputElement>) => {
    const newValue = e.currentTarget.value;
}

그 이유는 여기에서 읽을 수 있습니다 ( "Revert"Make SyntheticEvent.currentTarget. " ).

UPD : @ roger-gusmao가 언급했듯이 ChangeEvent양식 이벤트를 입력하는 데 더 적합합니다.

onChange = (e: React.ChangeEvent<HTMLInputElement>)=> {
   const newValue = e.target.value;
}

---

TypeScript에서 사용하는 올바른 방법은

  handleChange(e: React.ChangeEvent<HTMLInputElement>) {
    // No longer need to cast to any - hooray for react!
    this.setState({temperature: e.target.value});
  }

  render() {
        ...
        <input value={temperature} onChange={this.handleChange} />
        ...
    );
  }

전체 수업을 따르십시오. 이해하는 것이 좋습니다.

import * as React from "react";

const scaleNames = {
  c: 'Celsius',
  f: 'Fahrenheit'
};


interface TemperatureState {
   temperature: string;
}

interface TemperatureProps {
   scale: string;

}

class TemperatureInput extends React.Component<TemperatureProps, TemperatureState> {
  constructor(props: TemperatureProps) {
    super(props);
    this.handleChange = this.handleChange.bind(this);
    this.state = {temperature: ''};
  }

  //  handleChange(e: { target: { value: string; }; }) {
  //    this.setState({temperature: e.target.value});  
  //  }


  handleChange(e: React.ChangeEvent<HTMLInputElement>) {
    // No longer need to cast to any - hooray for react!
    this.setState({temperature: e.target.value});
  }

  render() {
    const temperature = this.state.temperature;
    const scale = this.props.scale;
    return (
      <fieldset>
        <legend>Enter temperature in {scaleNames[scale]}:</legend>
        <input value={temperature} onChange={this.handleChange} />
      </fieldset>
    );
  }
}

export default TemperatureInput;

---

as HTMLInputElement 나를 위해 일해

---

target당신이 추가하려고은 InputProps동일하지 않습니다 target에있는 당신이 원하는React.FormEvent

So, the solution I could come up with was, extending the event related types to add your target type, as:

interface MyEventTarget extends EventTarget {
    value: string
}

interface MyFormEvent<T> extends React.FormEvent<T> {
    target: MyEventTarget
}

interface InputProps extends React.HTMLProps<Input> {
    onChange?: React.EventHandler<MyFormEvent<Input>>;
}

Once you have those classes, you can use your input component as

<Input onChange={e => alert(e.target.value)} />

without compile errors. In fact, you can also use the first two interfaces above for your other components.

---

lucky i find a solution. you can

import { ChangeEvent } from 'react';

and then write code like: e:ChangeEvent<HTMLInputElement>

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Here is a way with ES6 object destructuring, tested with TS 3.3.
This example is for a text input.

name: string = '';

private updateName({ target }: { target: HTMLInputElement }) {
    this.name = target.value;
}

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This is when you're working with a FileList Object:

onChange={(event: React.ChangeEvent<HTMLInputElement>): void => {
  const fileListObj: FileList | null = event.target.files;
  if (Object.keys(fileListObj as Object).length > 3) {
    alert('Only three images pleaseeeee :)');
  } else {
    // Do something
  }

  return;
}}

---

  function handle_change(
    evt: React.ChangeEvent<HTMLInputElement>
  ): string {
    evt.persist(); // This is needed so you can actually get the currentTarget
    const inputValue = evt.currentTarget.value;

    return inputValue
  }

And make sure you have "lib": ["dom"] in your tsconfig.

참고URL : https://stackoverflow.com/questions/40676343/typescript-input-onchange-event-target-value