C#用数据库的列名而不是列值填充组合框 [英] C# Filling Combo box with Column name of Database not Column values

问题描述

我知道已经多次询问过这个问题，并且有很多关于此的资源，但相信我，我尝试过这些，不幸的是，总是会发生同样的事情.我真的不知道为什么我的组合框列值重复.有人可以帮助我以适当的方式做这些.我在这里忘记了什么吗?谢谢

I know it's been asked many times and there's so many resources about this but believe me i tried those, Unfortunately same thing is always happen. I really don't know why my combo box column value is repeating. Can someone help me in doing these in a proper way. Did i forgot something here ? Thank you

 public void FillComboBox()
  {
        using (var con = SQLConnection.GetConnection())
        {
            using (var cmd = new SqlCommand("SELECT * FROM employee_product", con))
            {
                using (var reader = cmd.ExecuteReader())
                {

                    while (reader.Read())
                    {
                        cbox_order.Items.Add("Code").ToString();
                        cbox_order.Items.Add("Model").ToString();
                        cbox_order.Items.Add("Itemdescription").ToString();
                    }

                }
            }
        }
  }

这是提供的图片

推荐答案

如果您检查代码，您基本上只是将字符串Code"、Model"和Itemdescription"添加到组合框.我猜你想要的是类似的东西:

If you check the code, you are basically just adding the strings "Code", "Model" and "Itemdescription" to the combobox. I guess you want rather something like:

while (reader.Read())
{
   cbox_order.Items.Add($"{reader["Code"]} {reader["Model"]} {reader["Itemdescription"]}");
}

在此代码段中，我使用 reader 从数据库中获取返回行中列的值，然后在单个 string 中显示连接这些值，即然后添加到 ComboBox 作为一个项目.

In this snippet I am using the reader to get values of the columns in the returned row from the DB and then displaying joining those values in a single string that is then added to the ComboBox as an item.

如果您知道列名，为什么不直接这样做?

If you know the column names, why not just do this?

public void FillComboBox()
{
    cbox_order.Items.Add("Code").ToString();
    cbox_order.Items.Add("Model").ToString();
    cbox_order.Items.Add("Itemdescription").ToString();
}

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