以編程方式在DropDownListControl中設置默認文本

Question

如何在程序中設置DropDownListControl中的默認文本？是否必須使用默認文本定義ValueField？

Answer 1

您可以通過多種方式編程設置默認的文本（即默認選擇項）：

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 

假設你DropDownList被命名爲dd

Answer 2

你可以做這樣的事情：

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);