- JavaScript
- XML
- Asynchronous Call to the server
Array : The ArrayList object is a
collection of items containing a single data value. Items are added to the
ArrayList with the Add() method. The capacity of an ArrayList is the number of
elements the list can hold. As elements are added to an ArrayList, the capacity
is automatically increased as required through reallocation. The capacity can be
decreased by calling Trim to Size or by setting the Capacity property
explicitly. Array are using for store similar data type grouping as a single
unit. We can access Array element by its numeric index. The array index start at
zero(0). The default value of numeric Array element are set to zero(0), and
reference element are set to null.
Syntax :
string[]
NAMES = new string[];
Step 1 : Open Visual Studio 2010.
- Go to File->New->WebSite.
- Select ASP.NET WebSite.
Step 2 : Go to Solution Explorer and
right-click.
- Select Add->New Item.
- Select WebForm.
- Default.aspx page open.
Step 3 : Now
go to the Default.aspx page and drag a control from Toolbox.
- Drag ScriptManger, UpdatePanel,
UpdateProgress,Button,Label
Step 4 : Now go to Default.aspx page and write
the below code.
Code :
<title>
My ajax application </title>
</head>
<body
bgcolor="#ffcccc">
<form
id="form1"
runat="server">
<asp:ScriptManager
ID="ScriptManager1"
runat="server"
/>
<div
style="background-color:
#CCFFCC">
<br
/>
<br
/>
<br
/>
<asp:UpdatePanel
ID="UpdatePanel1"
runat="server">
<ContentTemplate><fieldset><legend
style="background-color:
#00FFFF">Panel with Random Names</legend><br
/>
<asp:Button
ID="Button1" runat="server"
Text="Generate Random
Names"
OnClick="Button1_Click"
BorderColor="#660066"
/>
<br
/>
<asp:UpdateProgress
ID="UpdateProgress1"
runat="server"
DisplayAfter="100"
DynamicLayout="true">
<ProgressTemplate><img
border="1"
src=
"media.gif" src
= "Water lilies.jpg"/></ProgressTemplate>
</asp:UpdateProgress>
<asp:Label
ID="lblNames" runat="server"
ForeColor="#FF0066"></asp:Label>
</fieldset></ContentTemplate>
</asp:UpdatePanel>
</fieldset></ContentTemplate>
</asp:UpdatePanel>
Step 5 : Go to Default.aspx page and click in
Design option.
- Click in Button and select property option.
- Define the Text name.
Step 6 : Now go to default.aspx.cs page option
and write the below code.
Code :
using
System;
using
System.Collections.Generic;
using
System.Linq;
using
System.Web;
using
System.Web.UI;
using
System.Web.UI.WebControls;
public
partial class
_Default : System.Web.UI.Page
{
protected void
Page_Load(object sender,
EventArgs e)
{
}
private readonly
string[] NAMES = new
string[]
{
"MANISH",
"AMIT", "SACHIN",
"DINESH",
"PRAVEEN", "ADITYA", "ROHTASH",
"TEWATIA", "PRAVEEN", "NEHA",
"MONIKA", "akshay",
};
private void
FillListBoxRandom()
{
lblNames.Text = "";
List<String>
names = new List<string>();
int count = NAMES.Length;
for (int
i = 1; i < 4; i++)
{
System.Threading.Thread.Sleep(100);
Random rnd =
new Random();
int number = rnd.Next(count);
string selName = NAMES[number];
if (!names.Contains(selName))
{
names.Add(selName);
}
}
foreach
(string name in
names)
lblNames.Text += name + "<BR />";
}
protected void
Button1_Click(object sender,
EventArgs e)
{
FillListBoxRandom();
}
}
Step 7 : We add the following assembly
reference, because we are using a string array to store names.
Assembly :
using
System.Collections.Generic;
using
System.Collections;
Step 8 :
Now run the Web application by press F5.
Step 9 : We click on the Generate Random Names
option.
Now again click on the Generate Random Name option.