jQuery dynamically adds and deletes select items (implementation code)_jquery

Copy code The code is as follows:

// Add
function col_add() {
var selObj = $("#mySelect");
var value="value";
var text="text";
selObj.append("" text "");
}
// Delete
function col_delete() {
var selOpt = $("#mySelect option:selected");
selOpt.remove();
}
// Clear
function col_clear() {
var selOpt = $("#mySelect option");
selOpt.remove();
}

The above methods are for jQuery to dynamically add, delete and clear selection. The following is how to write pure js:

Copy code The code is as follows:

var sid = document. getElementById("mySelect");
sid.options[sid.options.length]=new Option("text","value"); // Add an item at the end of select

Other commonly used methods:

Copy code The code is as follows:

$("#mySelect") .change(function(){//code...}); //Triggered when the selected item changes

//Get the select value
var text=$("#mySelect").find("option:selected").text(); //Get the Text of the Select item
var value=$ ("#mySelect").val(); //Get the Value of the Select item
var value=$("#mySelect option:selected").attr("value"); //Get the Value of the Select item Value
var index=$("#mySelect").get(0).selectedIndex; //Get the index value of the Select option, starting from 0
var index=$("#mySelect option:selected" ).attr("index"); //Not available! ! !
var index=$("#mySelect option:selected").index(); //Get the index value of the Select option, starting from 0
var maxIndex=$("#mySelect option:last") .attr("index"); //Not available! ! !
var maxIndex=$("#mySelect option:last").index();//Get the Select maximum index value, starting from 0
$("#mySelect").prepend("text"); //Insert an item before the first item in Select

//Set the select value
//Set the selected item according to the index
$("#mySelect").get(0).selectedIndex=index;//index is the index value
//According to value sets the selected item
$("#mySelect").attr("value","newValue");
$("#mySelect").val("newValue");
$(" #mySelect").get(0).value = value;
//Set the corresponding item as the selected item according to the text
var count=$("#mySelect option").length;
for( var i=0;i{
if($("#mySelect").get(0).options[i].text == text)
{
$("#mySelect").get(0).options[i].selected = true;
break;
}
}

// Clear selection
$("#mySelect").empty();