c# - 来自数据库的下拉列表，如何合并 DataTextField 的列？

Question

我有一个从数据库中填充的下拉列表。当我只想在下拉列表的 DataTextField 中显示名字时，我可以使用它。但是如果我想显示 2 个字段，名字和姓氏，则会抛出错误。为什么这不起作用或我怎样才能让它起作用？

SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["ConString"].ConnectionString);
SqlCommand cmd = new SqlCommand("SELECT * FROM tbl_customers", con);
DataSet ds = new DataSet();
SqlDataAdapter da = new SqlDataAdapter(cmd);
con.Open();
da.Fill(ds, "Customers");
CustomerList.DataSource = ds.Tables[0];
CustomerList.DataTextField = "FirstName" + " " + "LastName";
CustomerList.DataValueField = "CID";
CustomerList.DataBind();

Answer 1

您必须从数据库中选择“虚拟”列:

string sql = @"SELECT FirstName + ' ' + LastName AS FullName, 
                      CID, FirstName, LastName  
               FROM tbl_customers 
               ORDER BY FullName ASC;"
SqlCommand cmd = new SqlCommand(sql, con);
// ...
CustomerList.DataSource = ds.Tables[0];
CustomerList.DataTextField = "FullName";
CustomerList.DataValueField = "CID";
CustomerList.DataBind();