1. Objects use this.$set() to modify and add:
obj: { name: "Xiao Ming", age: 18, }, //object
eg: this.$set(object that needs to be changed, "object attribute that needs to be changed", "new value")
1. Object modification
this.$set(this.obj, "name", "小刘");
//控制台输出：obj: { name: "小刘", age: 18, },2. Add new objects
this.$set(this.obj, "hobby", "study");
//控制台输出：obj: { name: "小明", age: 18, hobby: "study"}, 3. The new object is unknown (the item here is the parameter passed without quotation marks , and "reading" is the parameter value)
this.$set(this.obj, item, "reading");
2. Use this.$set() to modify and add arrays:
arr: [ //Array object
{ name: "小王", age: 18 },
{ name: "Xiao Zhang", age: 20 },
],
twoArr: [11, 22, 33, ], //ordinary array
eg: this.$set (array that needs to be modified, array subscript that needs to be modified, { "array object to be modified, one/multiple" })
1. Array modification
数组对象：
this.$set(this.arr, 1, { name: "小王", age: 19 });
//控制台输出：arr: [ { name: "小王", age: 18 },{ name: "小王", age: 19 }, ],普通数组：
this.$set(this.twoArr, 0, 99);
//控制台输出：twoArr: [99, 22, 33, ], 2. Added array
(1) First get the length of the array that needs to be added:
let reslg = this.arr.length; (2) Then add at the end of the array:
this.$set(this.arr, reslg,{ name: "小紫", age: 18 },);
//控制台输出：
arr: [
{ name: "小王", age: 18 },
{ name: "小张", age: 20 },
{ name: "小紫", age: 18 },
],In the same way, you can use this when the array or object is not updated when deleting:
this.$delete(this.obj, "name")