在我的react和typescript应用程序中，我使用:
onChange={(e) => data.motto = (e.target as any).value}
我如何正确地定义类的类型，这样我就不必用任何类型系统来破解我的方法?
export interface InputProps extends React.HTMLProps<Input> {
...
}
export class Input extends React.Component<InputProps, {}> {
}
如果我放target: {value: string};我得到:
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'.
由于@haind
是的HTMLInputElement为输入字段工作
//Example
var elem = e.currentTarget as HTMLInputElement;
elem.setAttribute('my-attribute','my value');
elem.value='5';
这个htmllinputelement的接口是继承自HTMLElement的，而HTMLElement是继承自根级别的EventTarget的。因此，我们可以根据上下文断言使用作为操作符来使用特定的接口，比如在这种情况下，我们使用HTMLInputElement作为输入字段，其他接口可以是HTMLButtonElement, HTMLImageElement等。
更多的参考，你可以检查其他可用的接口在这里
Mozilla的Web API接口
微软提供的外部节点模块接口
在TypeScript中使用的正确方法是
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} />
...
);
}
遵循完整的类，更好地理解:
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;
import { NativeSyntheticEvent, TextInputChangeEventData,} from 'react-native';
// Todo in java script
const onChangeTextPassword = (text : any) => {
setPassword(text);
}
// Todo在类型脚本中使用这个
const onChangeTextEmail = ({ nativeEvent: { text },}: NativeSyntheticEvent<TextInputChangeEventData>) => {
console.log("________ onChangeTextEmail _________ "+ text);
setEmailId(text);
};
<TextInput
style={{ width: '100%', borderBottomWidth: 1, borderBottomColor: 'grey', height: 40, }}
autoCapitalize="none"
returnKeyType="next"
maxLength={50}
secureTextEntry={false}
onChange={onChangeTextEmail}
value={emailId}
defaultValue={emailId}
/>
