Jquery operations such as select, checkbox, and radio are described in detail!

I. Select

Jquery gets the selected text and value of select:

1. $ ("# select_id"). Change (function () {// code...}); // Add an event for select, triggered when one of the select events is selected
2. var checktext = $ ("# select_id"). Find ("option: Selected"). Text (); // obtain the selected text
3. var checkvalue = $ ("# select_id"). Val (); // obtain the value selected by select
4. var checkindex = $ ("# select_id"). Get (0). selectedindex; // obtain the index value selected by select
5. var maxindex = $ ("# select_id option: Last"). ATTR ("Index"); // obtain the largest index value of select.

 

Jquery sets the text and value selected by select:

1. $ ("# select_id"). Get (0). selectedindex = 1; // select an item whose select index value is 1
2. $ ("# select_id"). Val (4); // select an item whose value is set to 4.
3. $ ("# select_id option [TEXT = 'jquery ']"). ATTR ("selected", true); // set the select text value to jquery.

 

Jquery adds/deletes select option items:

1. $ ("# select_id"). append ("<option value = 'value'> text </option>"); // append an option for select (drop-down)
2. $ ("# select_id "). prepend ("<option value = '0'> select </option>"); // insert an option for select (first position)
3. $ ("# select_id option: Last"). Remove (); // Delete the largest option (last) index value in select)
4. $ ("# select_id option [Index = '0']"). Remove (); // Delete the option with the index value 0 in select (the first option)
5. $ ("# select_id option [value = '3']"). Remove (); // Delete the option with value = '3' In the SELECT statement
6. $ ("# select_id option [TEXT = '4']"). Remove (); // Delete the option of '4' text = '4' in select

7. $ ("# selectid"). Remove (); // delete all items

Ii. checkbox

Select All/cancel

Jquery. ATTR gets/Sets object attribute values, such:
 

$ ("Input [name = 'chk _ list']"). ATTR ("checked"); // read the status of all objects whose names are 'chk _ List' (whether or not selected)
$ ("Input [name = 'chk _ list']"). ATTR ("checked", true); // set the checked value of all objects whose names are 'chk _ list' to true.
$ ("# Img_1"). ATTR ("src", "test.jpg"); // set the value of srcto 'test.jpg 'with the ID of img_1'
$ ("# Img_1"). ATTR ("src"); // read the SRC value whose ID is img_1

The following code gets the value of the checkbox selected in the above instance:
<SCRIPT type = "text/JavaScript">
$ (Document). Ready (function (){
VaR arrchk = $ ("input [name = 'chk _ list'] [checked]");
$ (Arrchk). Each (function (){
Window. Alert (this. value );
});
});
</SCRIPT>

1. Get the checkbox Value

$ ("# Checkboxid"). value or $ ("input [type = 'checkbox']"). eq (N). ATTR ("checked"). Value

2. Set the selected items

$ ("Input [type = 'checkbox']"). eq (1). ATTR ("checked") // you can specify the first checkbox as the selected item.

3. Delete all checkpoints.

$ ("Input [type = 'checkbox']"). Remove ()

4. checkbox Method

$ (Document). Ready (function (){
VaR check = $ ("input [type = 'checkbox']");
Check. Each (function (n ){
Check. eq (N). BIND ("click", function (){
If (check. eq (N). ATTR ("checked ")! = False ){
VaR value = check. eq (N). Val ();
Alert (value );
}
Else {
Alert (check. eq (N). ATTR ("checked "));
}
})
});
});

3. radio1: Obtain the selected value.

$ ("Input [type = 'Radio ']: checked"). Val ();
 

2. Set the specified item to the selected item.

$ ("Input [type = 'Radio ']"). eq (1). ATTR ("checked", true); // set the second item to the selected item

$ ("Input [type = 'Radio '] [value = 'value']"). ATTR ("checked, true"); 3, solves multiple radio
$ ("Input [type = 'Radio '] [@ name = 'rdotest2']"). eq (0). ATTR ("checked", true );