ashx hnadler error while paasing request and response [Resolved]

Hi aaryan try this

<asp:Image ID="id" runat="server" ImageUrl='<%# "Handler2.ashx?id=" + Eval("id")%>' />



<%@ WebHandler Language="C#" Class="Handler2" %>



using System;

using System.Web;

using System.Data.SqlClient;

using System.Windows.Forms;



public class Handler2 : IHttpHandler {



public void ProcessRequest(HttpContext context)



{



SqlConnection cn = new SqlConnection("Data Source=PRAVIN-PC;Initial Catalog=sales;Integrated Security=True");



cn.Open();

if (context.Request.QueryString["id"] != null)

{

string id1 = context.Request.QueryString["id"].ToString();







SqlCommand cmd = new SqlCommand("SELECT [image] FROM [image] where id =" + id1, cn);





SqlDataReader dr = cmd.ExecuteReader();



dr.Read();





if (dr["image"] != null || dr["image"] != DBNull.Value || !string.IsNullOrEmpty(dr["image"].ToString().Trim()))

{



context.Response.BinaryWrite((byte[])dr["image"]);



}





dr.Close();

}

cn.Close();



}

public bool IsReusable {

get {

return false;

}

}



} 

Himanshu Manjarawala
Sr. Software Engineer@AutomationAnywhere
http://fieredotnet.wordpress.com/

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Hi Aaryan,
I've doubt in your query.
you might get null result in "image field.
kindly check it

Himanshu Manjarawala
Sr. Software Engineer@AutomationAnywhere
http://fieredotnet.wordpress.com/

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Thanks for ur reply

yes.. am getting id value and the image value null... how to overcome it...

also canu u tell how to give dataimageurlformatstrieng field server map path to load file in grid

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Here is the solution:

public void ProcessRequest(HttpContext context)

{

SqlConnection cn = new SqlConnection("Data Source=PRAVIN-PC;Initial Catalog=sales;Integrated Security=True");

cn.Open();

string id1 =context.Request.QueryString["id"].ToString ();

SqlCommand cmd = new SqlCommand("SELECT [image] FROM [image] where id =" + id1, cn);

SqlDataReader dr = cmd.ExecuteReader();

dr.Read();

if(dr[image] != null || dr[image] != DBNull.Value)

{

context.Response.BinaryWrite((byte[])dr[image]);

}

dr.Close();

cn.Close();

} 

and now plz specify your second question in detail.

mark this as answer, if it helps you............

Himanshu Manjarawala
Sr. Software Engineer@AutomationAnywhere
http://fieredotnet.wordpress.com/

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context.Response.BinaryWrite((byte[])dr["image"]);
in the above line am getting error as below
Unable to cast object of type 'System.DBNull' to type 'System.Byte[]'.

Note: image s my field name so i added " " to image does it makes any error..

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Hi Aarya, heve you put condition i mentioned in my previous post???

Himanshu Manjarawala
Sr. Software Engineer@AutomationAnywhere
http://fieredotnet.wordpress.com/

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s... can u say the solution

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Here is the solution:

public void ProcessRequest(HttpContext context)

{

SqlConnection cn = new SqlConnection("Data Source=PRAVIN-PC;Initial Catalog=sales;Integrated Security=True");

cn.Open();

string id1 =context.Request.QueryString["id"].ToString ();

SqlCommand cmd = new SqlCommand("SELECT [image] FROM [image] where id =" + id1, cn);

SqlDataReader dr = cmd.ExecuteReader();

dr.Read();

if(dr[image] != null || dr[image] != DBNull.Value)

{

context.Response.BinaryWrite((byte[])dr[image]);

}

dr.Close();

cn.Close();

} 

mark this as answer, if it helps you............

Himanshu Manjarawala
Sr. Software Engineer@AutomationAnywhere
http://fieredotnet.wordpress.com/

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context.Response.BinaryWrite((byte[])dr["image"]);
in the above line am getting error as below
Unable to cast object of type 'System.DBNull' to type 'System.Byte[]'.

Note: image s my field name so i added " " to image does it makes any error

Aaryan, if this helps please login to Mark As Answer. | Alert Moderator

Here is the solution:

public void ProcessRequest(HttpContext context)

{

SqlConnection cn = new SqlConnection("Data Source=PRAVIN-PC;Initial Catalog=sales;Integrated Security=True");

cn.Open();

string id1 =context.Request.QueryString["id"].ToString ();

SqlCommand cmd = new SqlCommand("SELECT [image] FROM [image] where id =" + id1, cn);

SqlDataReader dr = cmd.ExecuteReader();

dr.Read();

if(dr[image] != null || dr[image] != DBNull.Value || !string.IsNullOrEmpty(dr[image].ToString().Trim()))

{

context.Response.BinaryWrite((byte[])dr[image]);

}

dr.Close();

cn.Close();

} 

mark this as answer, if it helps you............

Himanshu Manjarawala
Sr. Software Engineer@AutomationAnywhere
http://fieredotnet.wordpress.com/

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string id1 =context.Request.QueryString["id"].ToString ();

in this line am getting as

Object reference not set to an instance of an object.

the value of id1 is showing as null when i checked using breakpoint.. how can i solve this

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check URL from where you redirected to this handler??

Himanshu Manjarawala
Sr. Software Engineer@AutomationAnywhere
http://fieredotnet.wordpress.com/

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<asp:Image ID="id" runat="server" ImageUrl='<%# "Handler2.ashx?id=" + Eval("id")%>' />

This s my url...
I dnt knw what is to be changed

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can u pls reply me

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I'm not getting where problem could be?

as such i see the code line is correct...
will you attach your code??

Himanshu Manjarawala
Sr. Software Engineer@AutomationAnywhere
http://fieredotnet.wordpress.com/

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this my gird code;
<asp:Image ID="id" runat="server" ImageUrl='<%# "Handler2.ashx?id=" + Eval("id")%>' />

this my handler code:
<%@ WebHandler Language="C#" Class="Handler2" %>

using System;
using System.Web;
using System.Data.SqlClient;
using System.Windows.Forms;

public class Handler2 : IHttpHandler {

public void ProcessRequest(HttpContext context)

{

SqlConnection cn = new SqlConnection("Data Source=PRAVIN-PC;Initial Catalog=sales;Integrated Security=True");

cn.Open();
if (context.Request.QueryString["id"].ToString() != null)
{
string id1 = context.Request.QueryString["id"].ToString();



SqlCommand cmd = new SqlCommand("SELECT [image] FROM [image] where id =" + id1, cn);


SqlDataReader dr = cmd.ExecuteReader();

dr.Read();


if (dr["image"] != null || dr["image"] != DBNull.Value || !string.IsNullOrEmpty(dr["image"].ToString().Trim()))
{

context.Response.BinaryWrite((byte[])dr["image"]);

}


dr.Close();
}
cn.Close();

}
public bool IsReusable {
get {
return false;
}
}

}

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can u help in setting dataimageurlformatstring using server mappath..

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pls rep me

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your aspx code must be this...

<asp:TemplateField HeaderText="Image">
<ItemTemplate>
<asp:Image ID="Image1" runat="server" ImageUrl='<%# "ImageHandler.ashx?id="+ Eval("id") %>'/>
</ItemTemplate>
</asp:TemplateField>


and handler code must be---->>

public class ImageHandler : IHttpHandler {

public void ProcessRequest (HttpContext context) {
string id1 = context.Request.QueryString["id"];
SqlConnection connection = new SqlConnection(ConfigurationManager.ConnectionStrings["connectionString"].ConnectionString);
connection.Open();
SqlCommand command = new SqlCommand("select Image from Image where id="+id1, connection);
SqlDataReader dr = command.ExecuteReader();
dr.Read();
context.Response.BinaryWrite((Byte[])dr[0]);
connection.Close();
context.Response.End();

}

public bool IsReusable {
get {
return false;
}
}



if your problem solved then mark this as answer....

sourabh

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thank u so much... bt am nt getting image... so far there is x mark. now am nt having that bt image is nt displayed why?

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Ok then post this Question in new forum

Himanshu Manjarawala
Sr. Software Engineer@AutomationAnywhere
http://fieredotnet.wordpress.com/

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Ok,
do one thing....
Creare one folder called Image in you application root directory.
Create all images that are in your Database, in this folder using hamdler and name them <your-id>.jpg or as per your choice
and then write below code:

<asp:Image ID="id" runat="server" ImageUrl='<%# "Image\" + Eval("id") + ".jpg" %>' />

Mark this as answer, if it helps you................

Himanshu Manjarawala
Sr. Software Engineer@AutomationAnywhere
http://fieredotnet.wordpress.com/

Aaryan, if this helps please login to Mark As Answer. | Alert Moderator