How to implement single-select, multiple-select and reverse-select in forms in ReactJS

This article mainly introduces examples of single-selection, multi-selection and reverse selection in ReactJS implementation forms. It is of great practical value. Friends in need can refer to it.

This article introduces the single-selection and multi-selection implementation of forms in ReactJS. I would like to share with you examples of reverse selection and hope it will be helpful to you.
The requirement is to implement single selection, reverse selection, multi-selection, and all clear operations on the list

...... 
 this.state = {
   //初始化空数组，表示已经选择的
   selectedStores:[],
  }

......

handleClick(e){

 const newSelection = e.target.value;//拿到点击的具体一项

 let newSelectionArray;//新建一个空数组

//判断点击项是否为选择状态，是的话清除选中状态

 if(this.state.selectedStores.indexOf(newSelection) > -1) {

  newSelectionArray =

  this.state.selectedStores.filter((s:any) => s !== newSelection)

} else {

//不是的话就加入新选择数组

  newSelectionArray =

  [...this.state.selectedStores, newSelection];

}

 this.setState({
// 新选择数组统一改为选中状态
  selectedStores: newSelectionArray

 });

}

The Array.prototype.indexOf() method returns the first index where a given element can be found in the array , if it does not exist, returns -1.

Syntax:

arr.indexOf(searchElement)
arr.indexOf(searchElement[, fromIndex = 0])

The Array.prototype.filter() method creates a new array containing all elements of the test implemented by the provided function.

Grammar:

var new_array = arr.filter(callback[, thisArg])

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