It should be noted that a lot of the code here is for versions before jquery 1.32 (later versions no longer support @), so just replace it with empty code and test it.
jQuery gets the Text and Value of Select:
Syntax explanation:
1. $("#select_id").change(function(){//code. ..}); //Add an event for Select, which is triggered when one of the items is selected
2. var checkText=$("#select_id").find("option:selected").text(); // Get the Text selected by Select
3. var checkValue=$("#select_id").val(); //Get the Value selected by Select
4. var checkIndex=$("#select_id ").get( 0).selectedIndex; //Get the index value selected by Select
5. var maxIndex=$("#select_id option:last").attr("index"); //Get the maximum index value of Select
jQuery sets the Text and Value of Select:
Syntax explanation:
1. $("#select_id ").get(0).selectedIndex=1; / /Set the item with Select index value to 1 to select
2. $("#select_id ").val(4); //Set the item with Select Value to 4 to select
3. $("#select_id ") option[text='jQuery']").attr("selected", true); //Set the Text value of Select to the jQuery item selected
jQuery to add/delete Select Option item:
Syntax explanation:
1. $("#select_id").append(""); //Append an Option (drop-down item) to Select
2. $("#select_id").prepend(""); //Insert an Option (first position) for Select
3. $("#select_id option :last").remove(); //Delete the Option with the largest index value in Select (the last one)
4. $("#select_id option[index='0']").remove(); //Delete The Option with index value 0 in Select (the first one)
5. $("#select_id option[value='3']").remove(); //Delete the Option with Value='3' in Select
5. $("#select_id option[text='4']").remove(); //Delete the Option with Text='4' in Select
//Traverse options and add and remove option
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{
$("").appendTo($("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 drop-down menu ID attribute value of the selected item in the menu
$("#select").empty();//Clear the drop-down box//$("#select").html('');
$(" ").appendTo("#select")//Add the option of the drop-down box
Explain 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';
It can be seen that anything starting with @ means that it is followed by 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
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
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 $( "
2222
").appendTo("#sel")//Add the option of the drop-down box
$("#sel").empty();//Clear Drop-down box
For more information, please refer to the following articles:Jquery Select Operation Method Collection Script House Special Edition

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