There are two methods, you can try the first one first:
method 1:
toggleRowExpansion(isExpansion) {
this.toggleRowExpansion_forAll(this.tableData, isExpansion );
},
toggleRowExpansion_forAll(data, isExpansion) {
data.forEach((item) => {
this.$refs.dataTreeList.toggleRowExpansion(item, isExpansion);
if (item.children != undefined && item.children != null) {
this.toggleRowExpansion_forAll(item.children, isExpansion);
}
});
},
1. Among them, tableData is table data;
2. dataTreeList is el-table component 3;
3. When isExpansion is true, it will be expanded, and if it is false, it will be collapsed.
Method 2:
Principle: It is equivalent to executing the click event of the expansion icon in front of the tree table cell:
let len = document.getElementsByClassName("el-table__expand-icon").length;
for (let index = 0; index < len; index++) {
if (document.getElementsByClassName("el-table__expand-icon")[index]) {
document
.getElementsByClassName("el-table__expand-icon")
[index].click();
}
}
Note: If it does not take effect, it can be placed in the this.$nextTick method.