Javascript 反应-复选框值未定义,尽管有默认值
我有一个小问题,它导致在第一个复选框之后选中的所有复选框上的Javascript 反应-复选框值未定义,尽管有默认值,javascript,reactjs,Javascript,Reactjs,我有一个小问题,它导致在第一个复选框之后选中的所有复选框上的size和maxarayelements未定义(如果未触及输入框)。如果未触摸它们,它们都将默认设置为1 因此,在沙盒中,选择一个数据模式,selectorField,选中一个框,只需选择lengthType,然后点击submit。对象将返回(在控制台中)并带有size和arrayElements的默认值1 现在,如果我选中另一个框,只需选择lengthType,然后点击submit,size和arrayElements值如果不被触摸,
size
和maxarayelements
未定义(如果未触及输入框)。如果未触摸它们,它们都将默认设置为1
因此,在沙盒中,选择一个数据模式,selectorField,选中一个框,只需选择lengthType,然后点击submit。对象将返回(在控制台中)并带有size
和arrayElements
的默认值1
现在,如果我选中另一个框,只需选择lengthType,然后点击submit,size
和arrayElements
值如果不被触摸,则返回未定义的值。它们应该默认为1。我确实有一个占位符
值设置为1,因此可能会产生误导。具体来说,输入上的值
属性值={this.state.size[lastCheckedFieldName]| | 1}
通过将默认值设置为1(如果未更改)来处理此问题。但出于某种原因,这并没有发生
这是重复问题
import React from "react";
import ReactDOM from "react-dom";
import { Checkbox, CheckboxGroup } from "react-checkbox-group";
import axios from "axios";
import "./styles.css";
const schemas = [{ name: "Phone Data", id: "1" }];
const data = {
data: {
id: "2147483601",
name: "Phone Data",
fields: [
{
name: "Callee #"
},
{
name: "Caller #"
},
{
name: "Duration"
}
]
}
};
class App extends React.Component {
constructor(props) {
super(props);
this.state = {
schemas: [],
fields: [],
size: {},
lengthType: {},
maxArrayElements: {},
fieldNames: [],
submitDisabled: true
};
this.onDataSchemaChange = this.onDataSchemaChange.bind(this);
this.handleSubmit = this.handleSubmit.bind(this);
this.handleCancel = this.handleCancel.bind(this);
}
componentDidMount() {
axios({
method: "get",
url: `/list/of/schemas`
})
.then(response => {
console.log(response);
this.setState({ schemas: schemas });
})
.catch(error => console.log(error.response));
}
onDataSchemaChange = event => {
const schema = this.state.schemas.find(
schema => schema.name === event.target.value
);
if (schema) {
axios({
method: "get",
url: ``
})
.then(response => {
console.log(response);
this.setState({
fields: data.data.fields,
selectedId: data.data.id
});
console.log(this.state.selectedId);
console.log(this.state.fields);
})
.catch(error => console.log(error.response));
}
};
onSizeChange = e => {
e.persist();
const { fieldNames } = this.state;
const lastCheckedFieldName = fieldNames[fieldNames.length - 1];
this.setState(
prevState => {
return {
size: {
...prevState.size,
[lastCheckedFieldName]: e.target.value
}
};
},
() => {
console.log(this.state.size);
}
);
console.log([e.target.name]);
};
onChangeMaxArrayElements = e => {
e.persist();
const { fieldNames } = this.state;
const lastCheckedFieldName = fieldNames[fieldNames.length - 1];
this.setState(
prevState => {
return {
maxArrayElements: {
...prevState.maxArrayElements,
[lastCheckedFieldName]: e.target.value
}
};
},
() => {
console.log(this.state.maxArrayElements);
}
);
console.log([e.target.name]);
};
handleSelectorFieldChange = event => {
this.setState({ selectorField: event.target.value });
};
handleCancel = event => {
event.target.reset();
};
fieldNamesChanged = newFieldNames => {
this.setState({
submitDisabled: !newFieldNames.length,
fieldNames: newFieldNames,
size: {
[newFieldNames]: 1,
...this.state.size
},
maxArrayElements: {
[newFieldNames]: 1,
...this.state.maxArrayElements
}
});
console.log(this.state.size);
console.log(this.state.maxArrayElements);
};
updateSelectorField = e => {
this.setState({ selectorField: e.target.value });
};
updateLengthType = e => {
e.persist();
const { fieldNames } = this.state;
const lastCheckedFieldName = fieldNames[fieldNames.length - 1];
console.log("e", e);
this.setState(prevState => {
const lengthType = { ...prevState.lengthType };
lengthType[lastCheckedFieldName] = e.target.value;
return {
lengthType
};
});
};
handleSubmit = event => {
event.preventDefault();
const fields = this.state.fieldNames.map(fieldName => ({
name: fieldName,
lengthType: this.state.lengthType[fieldName],
size: this.state.size[fieldName],
maxArrayElements: this.state.maxArrayElements[fieldName]
}));
console.log(fields);
};
render() {
const { schemas, fields, fieldNames, selectorField } = this.state;
const lastCheckedFieldName = fieldNames[fieldNames.length - 1];
return (
<div>
<form onSubmit={this.handleSubmit}>
<fieldset>
<legend>
<h2>QuerySchema Information</h2>
</legend>
<div className="info-boxes">
<div>
<label> Pick the dataschema to describe your data file:</label>{" "}
<select
name="schemaName"
value={this.state.value}
onChange={this.onDataSchemaChange}
>
<option value="">Choose Dataschema ...</option>
{schemas &&
schemas.length > 0 &&
schemas.map(schema => {
return <option value={schema.name}>{schema.name}</option>;
})}
</select>
</div>
</div>
</fieldset>
<fieldset>
<legend>
<h2> DataSchema Fields </h2>
</legend>
<div className="selectorField-div">
<div>
<label>Selector Field:</label>{" "}
<select
value={this.state.selectorField}
onChange={this.updateSelectorField}
required
>
<option value="">Pick Selector Field...</option>
{fields &&
fields.map(field => {
return <option value={field.name}>{field.name}</option>;
})}
</select>
</div>
{selectorField && (
<fieldset>
<div>
<legend>Choose field names</legend>
<CheckboxGroup
checkboxDepth={5}
name="fieldNames"
value={this.state.fieldNames}
onChange={this.fieldNamesChanged}
required
>
{fields &&
fields.map(field => {
return (
<li>
<Checkbox value={field.name} />
{field.name}
</li>
);
})}
</CheckboxGroup>
</div>{" "}
</fieldset>
)}
</div>
<div className="input-boxes">
{lastCheckedFieldName && (
<div>
<label>Length Type:</label>
<select
value={this.state.lengthType[lastCheckedFieldName] || ""}
onChange={this.updateLengthType}
required
>
<option value="">Select Length Type...</option>
<option value="fixed">Fixed</option>
<option value="variable">Variable</option>
</select>
</div>
)}
{lastCheckedFieldName && (
<div>
<label>Size:</label>
<input
value={this.state.size[lastCheckedFieldName] || 1}
onChange={this.onSizeChange}
type="number"
name="size"
min="1"
placeholder="1"
required
/>
</div>
)}
{lastCheckedFieldName && (
<div>
<label>MaxArray Elements:</label>
<input
value={
this.state.maxArrayElements[lastCheckedFieldName] || 1
}
onChange={this.onChangeMaxArrayElements}
type="number"
name="maxArrayElements"
placeholder="1"
min="1"
max="100"
required
/>
</div>
)}
</div>
</fieldset>
<div className="btn-group">
<span className="input-group-btn">
<button
className="btnSubmit"
handleSubmit={this.handleSubmit}
type="submit"
disabled={this.state.submitDisabled}
>
Submit{" "}
</button>
<button
className="btnReset"
handleCancel={this.handleCancel}
type="reset"
onClick={() => {
alert("Clearing current field values.");
}}
>
Reset
</button>
</span>
</div>
</form>
</div>
);
}
}
const rootElement = document.getElementById("root");
ReactDOM.render(<App />, rootElement);
从“React”导入React;
从“react dom”导入react dom;
从“反应复选框组”导入{Checkbox,CheckboxGroup};
从“axios”导入axios;
导入“/styles.css”;
常量模式=[{name:“电话数据”,id:“1”}];
常数数据={
数据:{
id:“2147483601”,
姓名:“电话数据”,
字段:[
{
姓名:“被叫人#”
},
{
姓名:“来电者#”
},
{
名称:“持续时间”
}
]
}
};
类应用程序扩展了React.Component{
建造师(道具){
超级(道具);
此.state={
模式:[],
字段:[],
大小:{},
长度类型:{},
maxArrayElements:{},
字段名:[],
提交:对
};
this.onDataSchemaChange=this.onDataSchemaChange.bind(this);
this.handleSubmit=this.handleSubmit.bind(this);
this.handleCancel=this.handleCancel.bind(this);
}
componentDidMount(){
axios({
方法:“获取”,
url:`/list/of/schemas`
})
。然后(响应=>{
控制台日志(响应);
this.setState({schemas:schemas});
})
.catch(error=>console.log(error.response));
}
onDataSchemaChange=事件=>{
const schema=this.state.schemas.find(
schema=>schema.name==event.target.value
);
if(模式){
axios({
方法:“获取”,
网址:``
})
。然后(响应=>{
控制台日志(响应);
这是我的国家({
字段:data.data.fields,
选择edid:data.data.id
});
console.log(this.state.selectedId);
console.log(this.state.fields);
})
.catch(error=>console.log(error.response));
}
};
onSizeChange=e=>{
e、 坚持();
const{fieldNames}=this.state;
const lastCheckedFieldName=fieldNames[fieldNames.length-1];
这是我的国家(
prevState=>{
返回{
尺寸:{
…prevState.size,
[lastCheckedFieldName]:e.target.value
}
};
},
() => {
console.log(this.state.size);
}
);
log([e.target.name]);
};
onChangeMaxArrayElements=e=>{
e、 坚持();
const{fieldNames}=this.state;
const lastCheckedFieldName=fieldNames[fieldNames.length-1];
这是我的国家(
prevState=>{
返回{
maxArrayElements:{
…prevState.maxArrayElements,
[lastCheckedFieldName]:e.target.value
}
};
},
() => {
console.log(this.state.maxarayelements);
}
);
log([e.target.name]);
};
handleSelectorFieldChange=事件=>{
this.setState({selectorField:event.target.value});
};
handleCancel=事件=>{
event.target.reset();
};
fieldNamesChanged=newFieldNames=>{
这是我的国家({
submitDisabled:!newFieldNames.length,
字段名:新字段名,
尺寸:{
[newFieldNames]:1,
…这个州的尺寸
},
maxArrayElements:{
[newFieldNames]:1,
…this.state.maxarayelements
}
});
console.log(this.state.size);
console.log(this.state.maxarayelements);
};
updateSelectorField=e=>{
this.setState({selectorField:e.target.value});
};
UpdateLengtype=e=>{
e、 坚持();
const{fieldNames}=this.state;
const lastCheckedFieldName=fieldNames[fieldNames.length-1];
控制台日志(“e”,e);
this.setState(prevState=>{
const lengthType={…prevState.lengthType};
lengthType[lastCheckedFieldName]=e.target.value;
返回{
长型
};
});
};
handleSubmit=事件=>{
event.preventDefault();
const fields=this.state.fieldNames.map(fieldName=>({
名称:fieldName,
lengthType:this.state.lengthType[fieldName],
大小:this.state.size[fieldName],
maxArrayElements:this.state.maxArrayElements[fieldName]
}));
console.log(字段);
};
render(){
const{schemas,fields,fieldNames,selectorField}=this.state;
const lastCheckedFieldName=fieldNames[fieldNames.length-1];
返回(
查询模式信息
选择数据模式来描述您的数据文件:{“”}
选择数据模式。。。
{模式&&
schemas.length>0&&
schemas.map(schema=>{
返回{schema.name};
})}
数据模式字段
选择器字段:{'}
选择选择器字段。。。
lengthType: {
"Callee #": "fixed",
"Caller #": "variable"
},
maxArrayElements: {
"Callee #,Caller #": 1,
"Callee #": 1
}
fieldNames: [
0: "Callee #"
1: "Caller #"
]
fieldNamesChanged = newFieldNames => {
this.setState({
submitDisabled: !newFieldNames.length,
fieldNames: newFieldNames,
size: {
[newFieldNames[newFieldNames.length - 1]]: 1,
...this.state.size
},
maxArrayElements: {
[newFieldNames[newFieldNames.length - 1]]: 1,
...this.state.maxArrayElements
}
});
};