以编程方式在DropDownListControl中设置默认文本

Question

如何在程序中设置DropDownListControl中的默认文本？是否必须使用默认文本定义ValueField？

Answer 1

您可以通过多种方式编程设置默认的文本（即默认选择项）：

1) dd.SelectedIndex = 0; // by using known index of a DropDownItem, where 0 is your index 

2) dd.Items[0].Selected = true; // by setting Selected = true; on an item at a known index, where 0 is your index 

3) dd.SelectedIndex = dd.Items.IndexOf(dd.Items.FindByText("my item")); // by using known Text value of a DropDownItem, where "my item" is the known text 

假设你DropDownList被命名为dd

Answer 2

你可以做这样的事情：

myDdl.Items.Insert(0, "Default text"); 

Answer 3

ListItem item =new ListItem(); 
item.Text = "Select . . ."; 
item.Value = "Select"; 
item.Selected = true; 

dropdownlist1.Items.Add(item);