Summary of three methods for obtaining control values ​​in Jquery_jquery

A Jquery method to obtain the server control value
Since the server control will randomly generate the client id after the ASP.NET web page is run, jquery is not easy to operate when obtaining it. , Googled it, and found the following three methods:

Server control code:

1. $("#<%=txtUserID.ClientID%>").val();

2. $("input[id*=txtUserID]").val();

3. $("*[id$=txtUserID]").val();

Two Jquery methods to obtain the control value

Value:

$("") is a jquery object, not a dom element
value is an attribute of dom element
jquery corresponds to val
val(): Get the first matching element current value.
val(val): Set the value of each matching element.
So, the code should be written like this:
Value: val = $("#id")[0].value;
Assignment:
$("#id ")[0].value = "new value";
or $("#id").val("new value");

Or this can also be done: val = $("#id").attr("value");
Get the value of a set of radio selected items

var item = $('input[@name=items][@checked]').val();
Get the text of the selected item in select
var item = $("select[@name =items] option[@selected]").text();
The second element of the select drop-down box is the currently selected value
$('#select_id')[0].selectedIndex = 1;
The second element of the radio radio group is the currently selected value
$('input[@name=items]').get(1).checked = true;

Get value:

Text box, text area: $("#txt").attr("value");
Multiple selection box checkbox: $("#checkbox_id").attr("value");
Radio group radio: $("input[@type=radio][@checked]").val();
Drop-down box select: $('#sel').val();

Control form elements:
Text box, text area: $("#txt").attr("value",'');//Clear content
$(" #txt").attr("value",'11');//Fill content

Multiple selection box checkbox: $("#chk1").attr("checked",'');//Unchecked
$("#chk2").attr( "checked",true);//Check
if($("#chk1").attr('checked')==undefined) //Judge whether it has been checked

Radio group radio: $("input[@type=radio]").attr("checked",'2');//Set the item with value=2 as the currently selected item
Drop-down box select: $("#sel").attr("value",'-sel3');//Set the item with value=-sel3 as the currently selected item
$ ("11112222").appendTo("#sel")//Add the option of the drop-down box

$("#sel").empty(); //Clear the drop-down box

Three Jquery methods to get the DropDownList value of the control

Copy code Code As follows:

 

 
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