在Update语句上混淆 [英] Confused on Update statement

问题描述

HI，



我创建了一个带有textboses和数据库的Web表单。我现在很困惑.....

I have created a web form with textboses and a database. I am confused now.....

when i created a table, i created it with UserID column and set primary key but on the web form i didnt included it..so i dont know if i must include it..if yes? can u please show me how as i have already done the coding

你可以告诉我，我必须作为初学者提高。





在下面找到我的代码..

You are allowed to tell me were i must improve as a begginer.


find my code below..

protected void btnUpdate_Click(object sender, EventArgs e)
    {
      try
      {
       SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["ConnectionString01"].ConnectionString);
       conn.Open();
       SqlCommand comm = new SqlCommand("Udate tblreg");
       comm.ExecuteNonQuery();
       txtuser.Text = "";
       txtPass.Text = "";
       txtFulln.Text = "";
       txtSurname.Text = "";
       txtemail.Text = "";
       dropCountry.SelectedItem.ToString();
       dropProvince.SelectedItem.ToString();

        conn.Close();

       Label1.Visible = true;
       Label1.Text = "Record Successfully Updated!!";
        }
        catch
        {
            Response.Write("Error Occurred!!");
        }
        finally
        {
            Response.Write("Executed");
        }



       
        
    }
}

推荐答案

UPDATE语句需要将数据实际放入字段中，将字段限制为您想要更改的字段是一个非常好的主意：

UPDATE statements need data to actually put into the fields, and it is a very good idea to limit the fields to just those you want to change:

using (SqlConnection con = new SqlConnection(strConnect))
    {
    con.Open();
    using (SqlCommand com = new SqlCommand("UPDATE myTable SET myColumn1=@C1, myColumn2=@C2 WHERE Id=@ID", con))
        {
        com.Parameters.AddWithValue("@ID", id);
        com.Parameters.AddWithValue("@C1", myValueForColumn1);
        com.Parameters.AddWithValue("@C2", myValueForColumn2);
        com.ExecuteNonQuery();
        }
    }

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