JQuery common operation codes_jquery

//Traverse options and add and remove options
function changeShipMethod(shipping){
　var len = $("select[@name=ISHIPTYPE] option").length
　 if(shipping.value != "CA"){
　 $("select[@name=ISHIPTYPE] option").each(function(){
　 if($(this).val() == 111){
$ (this).remove();
　 　　 }
　 });
　 }
else

　{
　　$("UPS Ground"). appendTo($("select[@name=ISHIPTYPE]"));
　 }
}


//Get the selection value of the drop-down menu

$( #testSelect option:selected').text();
or $("#testSelect").find('option:selected').text();
or $("#testSelect").val ();
/////////////////////////////////////////////// ////////////////////////
If you have a bad memory, you can save it:
1, drop-down box:

var cc1 = $(".formc select[@name='country'] option[@selected]").text(); //Get the text of the selected item in the drop-down menu (note the space in the middle)
var cc2 = $( '.formc select[@name="country"]').val(); //Get the value of the selected item in the drop-down menu
var cc3 = $('.formc select[@name="country"]' ).attr("id"); //Get the ID attribute value of the selected item in the drop-down menu
$("#select").empty();//Clear the drop-down box//$("#select") .html('');
$("1111").appendTo("#select")//Add the option of the drop-down box

Explain it a little:
1.select[@name='country'] option[@selected] means the option element with the selected attribute in the select element that has the name attribute,
and the attribute value is 'country';
can be seen Anything starting with @ means that what follows is an attribute.

2, radio button:
$("input[@type=radio][@checked]").val(); //Get the value of the selected item of the radio button (note the middle No spaces)
$("input[@type=radio][@value=2]").attr("checked",'checked'); //Set the radio button value=2 to the selected state. (Note that there is no space in the middle)

3, check box:
$("input[@type=checkbox][@checked]").val(); //Get the check box selected The value of the first item
$("input[@type=checkbox][@checked]").each(function(){ //Since multiple check boxes are generally selected, the output can be looped
alert($(this).val());
});

$("#chk1").attr("checked",'');//uncheck
$("#chk2").attr("checked",true);//Tick
if($("#chk1").attr('checked')==undefined){} // Determine whether it has been checked


Of course jquery's selector is powerful. There are many methods.






aaass



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jquery radio takes the value, checkbox takes the value Value, select value, radio selected, checkbox selected, select selected, and related to obtain 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();
select the item of the drop-down box The two elements are the currently selected value
$('#select_id')[0].selectedIndex = 1;
The second element of the radio radio selection group is the currently selected value
$('input[@ name=items]').get(1).checked = true;
Get value:
Text box, text area: $("#txt").attr("value");
Multiple Checkbox: $("#checkbox_id").attr("value");
Radio group radio: $("input[@type=radio][@checked]").val();
Drop-down box select: $('#sel').val();
Control form element:
Text box, text area: $("#txt").attr("value",'') ;//Clear content
$("#txt").attr("value",'11');//Fill content
Multiple selection box checkbox: $("#chk1").attr(" checked",'');//Unchecked
$("#chk2").attr("checked",true);//Checked
if($("#chk1").attr ('checked')==undefined) //Determine whether the
radio group radio has been checked: $("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 $("1111
2222
").appendTo("#sel")//Add the option of the drop-down box
$("#sel").empty( ); //Clear the drop-down box

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 current Selected value
$('#select_id')[0].selectedIndex = 1;
The second element of the radio radio selection 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 selection group radio: $("input[@type=radio][@checked]").val();
Drop-down box select: $('#sel').val();
Control form elements:
Text box, text area: $("#txt").attr("value",'');//Clear the content
$("#txt").attr("value",'11');//Fill content
Multiple selection box checkbox: $("#chk1").attr("checked",'' );//Unchecked
$("#chk2").attr("checked",true);//Checked
if($("#chk1").attr('checked') ==undefined) //Judge whether
radio group radio has been checked: $("input[@type=radio]").attr("checked",'2');//Set value=2 The item is the currently selected item drop-down box select: $("#sel").attr("value",'-sel3');//The item setting value=-sel3 is the currently selected item$( "1111
2222
").appendTo("#sel")//Add the option of the drop-down box
$("#sel").empty();//Clear Drop-down box
Introduction to the basics of jquery common operations
Jquery select (list) operations (value/assignment)