[转]dropdownlist动态绑定数据方法 添加默认项“请选择”

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《一》动态绑定方法
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: [1 I) V# F" c" r1 b/ XddlItems.DataSource = voe.SelectItems();
ddlItems.DataTextField = "VoteItem";
ddlItems.DataValueField = "VoteId";
ddlItems.DataBind();

《二》添加默认项“请选择”
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方法1
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绑定后添加
ListItem lt = new ListItem();
lt.Text = "请选择";
% x- K# `& E: ]$ m( P8 D% I" S" `lt.Value = "00";
( R8 E$ G' o$ i1 I% N  rlt.Selected = true;
ddl.Items.Add(lt);

放到databind()之后

7 v( j: ~  ?* f) o+ N方法2

% p8 {3 |2 F1 i: V绑定以后添加下面代码：
: e3 W6 e9 I+ W/ }: s! J! ~3 UListItem it = new ListItem("请选择", "0");
ddl.Items.Insert(0,it);

* D3 C5 [1 S: }' a《三》绑定后指定第一项
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8 |2 h7 T7 \# o4 L) w' a* DddlItems.DataSource = voe.SelectItems();
+ ]9 q5 n# d& `; R8 l; T, jddlItems.DataTextField = "VoteItem";
ddlItems.DataValueField = "VoteId";
ddlItems.DataBind();
string str="你想要的文本";
int index = this.ddl.Items.IndexOf(this.ddl.Items.FindByText(str));
; ]+ D) c- H* m9 Eddl.SelectedIndex = index;

- v" o$ @. C* M2 R9 O# n《三》绑定后指定第一项

" I  Q( O- T5 ?+ [* s1 wddlItems.DataSource = voe.SelectItems();
ddlItems.DataTextField = "VoteItem";
ddlItems.DataValueField = "VoteId";
ddlItems.DataBind();
string vID = Request.QueryString["id"];
5 L4 `$ J2 ^" r4 v6 m9 nddl.SelectedValue= vID;