ASP.NET

Quote:

f i click preview the data should be displayed.

From link[^]:

Basically, when you failed to connect to your SQL Server, the issue could be:
1) Network issue,
2) SQL Server configuration issue.
3) Firewall issue,
4) Client driver issue,
5) Application configuration issue.
6) Authentication and logon issue.

select count(*) from Table where username = 'Robert';DROP TABLE [Table];--'

// SqlConnection implements IDisposable, so wrap it in a "using" block:
using (SqlConnection cn = new SqlConnection(ConfigurationManager.ConnectionStrings["userConnectionString"].ConnectionString))
{
    cn.Open();
    
    // Use a parameterized query to avoid SQL injection:
    string sel = "select count(*) from [Table] where username = @username";
    
    // SqlCommand also implements IDisposable:
    using (SqlCommand com = new SqlCommand(sel, cn))
    {
        // Add the parameter to the command:
        com.Parameters.AddWithValue("@username", username.Text);
        
        int temp = Convert.ToInt32(com.ExecuteScalar());
        if (temp == 1)
        {
            Response.Write("User already exists..!!");
        }
    }
}

http://www.w3.org/TR/REC-html40/intro/sgmltut.html#h-3.3.4.2[^]

Some attributes play the role of boolean variables (e.g., the selected attribute for the OPTION element). Their appearance in the start tag of an element implies that the value of the attribute is "true". Their absence implies a value of "false".

Boolean attributes may legally take a single value: the name of the attribute itself (e.g., selected="selected").

In HTML, boolean attributes may appear in minimized form -- the attribute's value appears alone in the element's start tag. Thus, selected may be set by writing:

HTML

<OPTION selected>

instead of:

HTML

<OPTION selected="selected">

Authors should be aware that many user agents only recognize the minimized form of boolean attributes and not the full form.

Richard Deeming wrote:

What you're looking at is a boolean attribute: