Reader Level:
ARTICLE

Image Rotator in Ajax

On June 16, 2011 Articles | AJAX
In this article you will see how to use the Image Rotator in Ajax.
  • 1
  • 0
  • 4856


Step 1: In this Example, there is an Image (img1) and a TextBox(TextBox1).

<img id="img1" src="Image/1.jpg" /><br />

<asp:TextBox ID="TextBox1" runat="server">1</asp:TextBox>

ImgRorator1.gif

Image 1

Step 2: We call a function ChangeImage() on the onload event of the <body> tag. So when the page loads the function will be called automatiacally.

var xmlHttp
        var arr;
        function ChangeImage() {
            xmlHttp = GetXmlHttpObject()
            var url = "Default.aspx"
            url = url + "?iname=" + document.getElementById('TextBox1').value
            xmlHttp.onreadystatechange = stateChanged
            xmlHttp.open("GET", url, true)
            xmlHttp.send(null)
            return false;
        }


We set the Text property of TextBox1:

<asp:TextBox ID="TextBox1" runat="server">1</asp:TextBox>

Now we write the function ChangeImage():

ImgRorator2.gif

Now we can write the GetXmlHttpObject() to check the browser:

function GetXmlHttpObject() {
var objXMLHttp = null
if (window.XMLHttpRequest) {
objXMLHttp = new XMLHttpRequest()
}
else if (window.ActiveXObject) {
objXMLHttp = new ActiveXObject("Microsoft.XMLHTTP")
}
return objXMLHttp
}

ImgRorator3.gif

Step 3: In the Page_Load Event:

if (Request.QueryString["iname"] != null)
        {
            string i = Request.QueryString["iname"].ToString();
            string str = "1";
            if (i == "2")
            {

                str = "2";
            }

            Response.Clear();

            Response.Write(str);
            Response.End();
        }


Complete Program

Default.aspx


<head runat="server">
<title></title>
<
script language="JavaScript" type="text/javascript" >
var xmlHttp
var arr;
function ChangeImage() {
xmlHttp = GetXmlHttpObject()
var url = "Default.aspx"
url = url + "?iname=" + document.getElementById('TextBox1').value
xmlHttp.onreadystatechange = stateChanged
xmlHttp.open("GET", url, true)
xmlHttp.send(null)
return false;
}
function stateChanged() {

if (xmlHttp.readyState == 4 || xmlHttp.readyState == "complete") {

var str;

str = xmlHttp.responseText;

if (str == "1") {
document.getElementById("img1").src = "Image/211825_100000984069347_8367124_q.jpg";
document.getElementById("TextBox1").value = "2";
setTimeout("ChangeImage()", 1000);
}
if (str == "2") {
document.getElementById("img1").src = "Image/17Dec20100846PMfinal33.jpg";
setTimeout("ChangeImage()", 1000);
document.getElementById("TextBox1").value = "1";
}

}
}
function GetXmlHttpObject() {

var objXMLHttp = null
if (window.XMLHttpRequest) {
objXMLHttp = new XMLHttpRequest()
}
else if (window.ActiveXObject) {
objXMLHttp = new ActiveXObject("Microsoft.XMLHTTP")
}
return objXMLHttp
}

</script>

</head>
<
body onload="ChangeImage()">
<form id="form1" runat="server">
<div>

<img alt=""  id="img1"
style="height: 156px; width: 233px" src="Image/1.jpg" /><br />
<br />
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<asp:TextBox ID="TextBox1" runat="server">1</asp:TextBox>
<br />

</div>
</
form>
</
body>
</
html>

Default.aspx.cs

protected void Page_Load(object sender, EventArgs e)
{
if (Request.QueryString["iname"] != null)
{
string i = Request.QueryString["iname"].ToString();
string str = "1";
if (i == "2")
{

str = "2";
}

Response.Clear();

Response.Write(str);
Response.End();
}
}

Mahak Gupta

My name is Mahak Gupta. I am a C# Corner MVP.

  • 52rank
  • 1M readers
  • 2times
COMMENT USING

Trending up