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hi,

Can anyone know. why the following error comes.

Unable to cast object of type 'System.String' to type 'System.Byte[]'.how to solve?.how to solve?


code:

C#
public void ProcessRequest (HttpContext context) 
    {
       // SqlConnection cn = new SqlConnection(ConfigurationManager.ConnectionStrings["Connection"].ConnectionString);
        SqlConnection cn = new SqlConnection(ConfigurationManager.AppSettings["constring"].ToString());
        cn.Open();
        
      string sql = "Select clogo from tbl_company1 where cid=@cid";
        SqlCommand cmd = new SqlCommand(sql, cn);
       cmd.Parameters.Add("@cid", SqlDbType.Int).Value = context.Request.QueryString["cid"];
       cmd.Prepare();
        SqlDataReader dr = cmd.ExecuteReader();
       dr.Read();
       //context.Response.ContentType = dr["imagename"].ToString();
       context.Response.BinaryWrite((byte[])dr["clogo"]);//error is here like "Unable to cast object of type 'System.String' to type 'System.Byte[]'"//
       dr.Close();
       cn.Close(); 
        
   }
Posted
Updated 9-Feb-12 19:46pm
v3
Comments
uspatel 10-Feb-12 0:54am    
Question Heading Changed by OP.

1 solution

use as
C#
if(dr.Read())
{
       //context.Response.ContentType = dr["imagename"].ToString();
       context.Response.BinaryWrite((byte[])dr["clogo"]);//error is here//
}
 
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Comments
sathiyak 10-Feb-12 0:42am    
context.Response.BinaryWrite((byte[])dr["clogo"]);//here error comes like below:

Unable to cast object of type 'System.String' to type 'System.Byte[]'.
uspatel 10-Feb-12 0:53am    
These types are unrelated;See

http://www.codeproject.com/Questions/327497/Unable-to-cast-object-of-type-System-String-to-typ
sathiyak 10-Feb-12 0:57am    
these code are in vb.net...i need c# code..i dt know vb...
uspatel 10-Feb-12 0:55am    
check waht is your clogo type, is it image /binary
sathiyak 10-Feb-12 0:58am    
image type is varchar......do u the alternative code for below;
context.Response.BinaryWrite((byte[])dr["clogo"]);//here error comes like this//
if u know pls let me know...

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