Js,jquery get the value of the Select,dropdownlist,checkbox drop-down list box (sample code) _javascript Tips

jquery Gets the text and value selected by select:
Syntax Explanation:
1. $ ("#select_id"). Change (function () {//code ...}); Adds an event for a select that fires when one of the items is selected
2. Var checktext=$ ("#select_id"). Find ("option:selected"). Text (); Gets the text selected by select
3. Var checkvalue=$ ("#select_id"). Val (); Gets the value of the Select selection
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 for select

jquery Sets the Select selected text and value:
Syntax Explanation:
1. $ ("#select_id"). Get (0). selectedindex=1; To set the Select index value of 1
2. $ ("#select_id"). Val (4); Select to set the value of 4 for the Select
3. $ ("#select_id option[text= ' jQuery ']"). attr ("selected", true); Set the text value of select to the item selected for jquery

jquery Add/Remove option items for select:
Syntax Explanation:
1. $ ("#select_id"). Append ("<option value= ' value ' >Text</option>"); Append an option to select (dropdown)
2. $ ("#select_id"). Prepend ("<option value= ' 0 ' > Please select </option>"); Inserts an option for the Select (first position)
3. $ ("#select_id option:last"). Remove (); Delete index value maximum option (last) in select
4. $ ("#select_id option[index= ' 0 ']"). Remove (); Delete option with index value of 0 in select (first)
5. $ ("#select_id option[value= ' 3 ']"). Remove (); Delete option value= ' 3 ' in select
5. $ ("#select_id option[text= ' 4 ']"). Remove (); Delete option text= ' 4 ' in select

jquery Radio value, checkbox value, select Value, Radio selected, CheckBox selected, select selected, and related
Gets the value of a set of radio selected items
var item = $ (' input[@name =items][@checked] '). Val ();
Gets the text of the Select selected item
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;
Radio the second element of a 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 ();
Dropdown box Select: $ (' #sel '). Val ();

Control form elements:
text box, text area: $ ("#txt"). attr ("Value", "");/empty content
$ ("#txt"). attr ("value", ' 11 ');//fill content

Multi-Marquee checkbox: $ ("#chk1"). attr ("Checked", "");/no tick.
$ ("#chk2"). attr ("Checked", true);/tick
if ($ ("#chk1"). attr (' checked ') ==undefined)//judge whether it has been ticked

Single-select group radio: $ ("input[@type =radio]"). attr ("Checked", ' 2 ');//Set value=2 project is currently selected
Dropdown box Select: $ ("#sel"). attr ("value", '-sel3 ');//Set VALUE=-SEL3 item as current selection
$ ("<option value= ' 1 ' >1111</option><option value= ' 2 ' >2222</option>"). Appendto ("#sel")// Option to add a drop-down box
$ ("#sel"). empty ();//Empty Drop-down box

-------------------------------------------------------------------

Traversing option and adding, removing 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{
$ ("<option value= ' >ups ground</option>"). Appendto ($ ("select[@name =ishiptype]");
}
}

Get the Select value of the Drop-down menu

$ (#testSelect option:selected '). Text ();
or $ ("#testSelect"). Find (' option:selected '). Text ();
or $ ("#testSelect"). Val ();
//////////////////////////////////////////////////////////////////

a bad memory can be collected:
1, dropdown box:

var cc1 = $ (". FORMC select[@name = ' country '] option[@selected]"). Text (); Gets the text of the selected item in the Drop-down menu (note that there are spaces in the middle)
var CC2 = $ ('. FORMC select[@name = ' country '] '). Val (); Gets the value of the selected item in the Drop-down menu
var cc3 = $ ('. FORMC select[@name = ' country '] '). attr ("id"); Gets the id attribute value of the selected item in the Drop-down menu
$ ("#select"). Empty ()//Empty Drop-down box//$ ("#select"). HTML (");
$ ("<option value= ' 1 ' >1111</option>"). Appendto ("#select")//option to add a drop-down box

A little explanation:
1.select[@name = ' country '] option[@selected] Represents the Name property,
and the attribute value is the option element with the selected attribute inside the Select element of ' country ';
It can be seen that a @ begins with a property that follows.

2, Radio Box:
$ ("input[@type =radio][@checked]"). Val (); Gets the value of the selected item in the Radio box (note that there are no spaces in the middle)
$ ("input[@type =radio][@value =2]"). attr ("Checked", ' checked '); Sets the value=2 of the radio box to the selected state. (Note that there are no spaces in between)

3, check box:
$ ("input[@type =checkbox][@checked]"). Val (); Gets the value of the first item selected in the check box
$ ("input[@type =checkbox][@checked]"). each (function () {//, because the check box is typically selected for more than one, you can cycle the output
Alert ($ (this). Val ());
});

$ ("#chk1"). attr ("Checked", "");/no tick.
$ ("#chk2"). attr ("Checked", true);/tick
if ($ ("#chk1"). attr (' checked ') ==undefined) {}//judge whether it has been ticked

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

<script src= "Jquery-1.2.1.js" type= "Text/javascript" ></script>
<script language= "javascript" type= "Text/javascript" >
$ (document). Ready (function () {
$ ("#selectTest"). Change (function ()
{
Alert ("Hello");
Alert ($ ("#selectTest"). attr ("name"));
$ ("a"). attr ("href", "xx.html");
Window.location.href= "xx.html";
Alert ($ ("#selectTest"). Val ());
Alert ($ ("#selectTest option[@selected]"). text ());
$ ("#selectTest"). attr ("Value", "2");

});
});
</script>

<a href= "#" >aaass</a>

<!--dropdown box-->
<select id= "Selecttest" name= "Selecttest" >
<option value= "1" >11</option>
<option value= "2" >22</option>
<option value= "3" >33</option>
<option value= "4" >44</option>
<option value= "5" >55</option>
<option value= "6" >66</option>
</select>

jquery Radio value, checkbox value, select Value, Radio selected, CheckBox selected, select selected, and related to get a set of radio selected values
var item = $ (' input[@name =items][@checked] '). Val ();
Gets the text of the Select selected item
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;
Radio the second element of a 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 ();
Dropdown box Select: $ (' #sel '). Val ();

controls the form element:
text box, text area: $ ("#txt"). attr ("Value", "");/empty contents
$ ("#txt"). attr ("value", ' 11 '); Fill content
Multiple-selection box checkbox: $ ("#chk1"). attr ("Checked", "");/no tick
$ ("#chk2"). attr ("Checked", true);/tick
if ($ ("#chk1 "). attr (' checked ') ==undefined)//To determine if it has been ticked
Radio Group Radio: $ (" input[@type =radio] "). attr (" Checked ", ' 2 ');//Set value= 2 of the item is currently selected
Drop-down box select: $ ("#sel"). attr ("value", '-sel3 ');//Set VALUE=-SEL3 project is current selected
$ ("< Optionvalueoptionvalue= ' 1 ' >1111</option><optionvalueoptionvalue= ' 2 ' >2222</option> '). Appendto ("#sel")/Option
$ ("#sel") to add a Drop-down box. Empty ()//Empty Drop-down box

Get a set of radio selected values
var item = $ (' input[@name = Items][@checked]. Val ();
Get text for select selected Item
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 ();
Dropdown box Select: $ (' #sel '). Val ();

Control form elements:
text box, text area: $ ("#txt"). attr ("Value", "");/empty content
$ ("#txt"). attr ("value", ' 11 ');//fill content
Multi-Marquee checkbox: $ ("#chk1"). attr ("Checked", "");/no tick.
$ ("#chk2"). attr ("Checked", true);/tick
if ($ ("#chk1"). attr (' checked ') ==undefined)//judge whether it has been ticked
Single-select group radio: $ ("input[@type =radio]"). attr ("Checked", ' 2 ');//Set value=2 project is currently selected
Dropdown box Select: $ ("#sel"). attr ("value", '-sel3 ');//Set VALUE=-SEL3 item as current selection
$ ("<option value= ' 1 ' >1111</option><option value= ' 2 ' >2222</option>"). Appendto ("#sel")// Option to add a drop-down box
$ ("#sel"). empty ();//Empty Drop-down box