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using (con)
{
con.Open();
String sqltext = "select * from emp where empno=@empno";
SqlCommand cmd = new SqlCommand(sqltext, con);
cmd.Parameters.AddWithValue("@empno", this.TextBox.Text);
GridView1.DataSource = cmd.ExecuteReader();
GridView1.DataBind();
}
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@tablename nvarchar(50),
@fieldname nvarchar(50)='*',
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MySQL: SUBSTR(), SUBSTRING()
Oracle: SUBSTR()
SQL Server: SUBSTRING()
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