updating a row in datagrid..

Hi everyone,
I'm having with selecting a row in a datagrid. I have a datagrid that
is ment to update and it runs very well, But I don't want the user to
keep scrolling when ever they want to update so I created a
textbox(txtname) and a button where a user is supposed to write a name
and by the click of the button the corresponding row is selected. Now
where the problem is it's that when I write a name say
Ndayahundwa,Claude and press button I get this error:
Incorrect syntax near 'Ndayahundwa'. Here is the code I'm using:

SqlCommand myCommand = new SqlCommand();
myCommand.Connection=con;
myCommand.CommandText="select * from isp_email.staff where @fullname
like%" +txtname.Text+ "%";
SqlParameter myparam = new SqlParameter("@fullname",SqlDbType.Text);
myparam.Value=txtname.Text;
myCommand.Parameters.Add(myparam);
SqlDataAdapter myAdapter=new SqlDataAdapter(myCommand);
DataSet ds = new DataSet();
myAdapter.Fill(ds);
dgupdate.DataSource=ds;
dgupdate.DataBind();
Could some one bail me out?
Thanks.

.

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