Date linkage implementation code for jquery select operation_jquery

Jquery's selector is very powerful. When adding the options object of select, I searched for a long time before I found

Copy code The code is as follows :

/**//*
File name: jquery.liu.select.js
Function description: This js file is a plug-in of the jquery class library, which mainly implements the operation of select.
Author: John Liu
Writing date: 2008/03/12
*/
//Get the number of select items
jQuery.fn.size = function()
{
return jQuery (this).get(0).options.length;
}
//Get the index of the selected item
jQuery.fn.getSelectedIndex = function()
{
return jQuery(this ).get(0).selectedIndex;
}
//Get the text of the currently selected item
jQuery.fn.getSelectedText = function()
{
if(this.size() == 0)
{
return "No options in the drop-down box";
}
else
{
var index = this.getSelectedIndex();
return jQuery( this).get(0).options[index].text;
}
}
//Get the value of the currently selected item
jQuery.fn.getSelectedValue = function()
{
if(this.size() == 0)
{
return "No selected value in the drop-down box";
}
else
{
return jQuery(this ).val();
}
}
//Set the item with value in select to be selected
jQuery.fn.setSelectedValue = function(value)
{
jQuery (this).get(0).value = value;
}
//Set the first item with text in select to be selected
jQuery.fn.setSelectedText = function(text)
{
var isExist = false;
var count = this.size();
for(var i=0;i{
if(jQuery(this) .get(0).options[i].text == text)
{
jQuery(this).get(0).options[i].selected = true;
isExist = true;
break;
}
}
if(!isExist)
{
alert("This item does not exist in the drop-down box");
}
}
//Set the selected index item
jQuery.fn.setSelectedIndex = function(index)
{
var count = this.size();
if(index >= count || index < 0)
{
alert("Selected item index out of range");
}
else
{
jQuery(this).get(0).selectedIndex = index ;
}
}
//Determine whether there is an item with value in the select item
jQuery.fn.isExistItem = function(value)
{
var isExist = false;
var count = this.size();
for(var i=0;i{
if(jQuery(this).get(0).options[i ].value == value)
{
isExist = true;
break;
}
}
return isExist;
}
//Add to select One item, the displayed content is text and the value is value. If the item value already exists, it will prompt
jQuery.fn.addOption = function(text,value)
{
if(this.isExistItem(value ))
{
alert("The value of the item to be added already exists");
}
else
{
jQuery(this).get(0).options.add (new Option(text,value));
}
}
//Delete the item with value in the select. If the item does not exist, it will prompt
jQuery.fn.removeItem = function (value)
{
if(this.isExistItem(value))
{
var count = this.size();
for(var i=0;i{
if(jQuery(this).get(0).options[i].value == value)
{
jQuery(this).get(0).remove(i );
break;
}
}
}
else
{
alert("The item to be deleted does not exist!");
}
}
//Delete the item with the specified index in select
jQuery.fn.removeIndex = function(index)
{
var count = this.size();
if(index > = count || index < 0)
{
alert("The index of the item to be deleted is out of range");
}
else
{
jQuery(this).get( 0).remove(index);
}
}
//Remove the selected item in select
jQuery.fn.removeSelected = function()
{
var index = this.getSelectedIndex();
this.removeIndex(index);
}
//Clear all items in the select
jQuery.fn.clearAll = function()
{
jQuery(this).get(0).options.length = 0;
}