請問,DropDownList怎麼做到把從數據庫中取出來的值顯示出來,而其他項點下來標誌的時候也還存在

Question

you can like this:eg:
<asp:DropDownList id="ddlCountry" DataSource="<%# BindTheCountry() %>"  DataTextField="Country" DataValueField="Country" runat="server" />public SqlDataReader BindTheCountry()
{
SqlConnection objConn=new SqlConnection("server=data;uid=run1;pwd=benben;database=Northwind");
SqlCommand cmdCustomers=new SqlCommand("SELECT Distinct Country FROM Customers",objConn);
cmdCustomers.CommandType=CommandType.Text;
objConn.Open();
return (cmdCustomers.ExecuteReader(CommandBehavior.CloseConnection));
}

Answer 1

DropDownList1.DataTextField="name";
DropDownList1.DataValueField="id";
绑定数据库的一个字段.name
protected void Select_Changded(object sender,EventArgs e)
{
             Textbox1.Text=DropDownList1.SelectedItem.Text;
}

Answer 2

SqlConnection Connection=new SqlConnection(.....);
Connection.Open();
SqlCommand myCommand=new SqlCommand("selectName",Connection);
myCommand.CommandType=CommandType.StoredProcedure;
myCommand.ExecuteNonQuery();
SqlDataAdapter sda=new SqlDataAdapter();
sda.SelectCommand=myCommand;
DataSet ds=new DataSet();
sda.Fill(ds,"em");

Connection.Dispose();
DropDownList1.DataSource=ds;
DropDownList1.DataTextField="name";
DropDownList1.DataValueField="id";
DropDownList1.DataBind();

Answer 3

各位大哥,我還是不是很明白,我的各個item項是從前台添加的,所以,我還是實現不了.

Answer 4

你从数据库读出数据以后
先建立一个listitem
ListItem li = new ListItem();
然后用你的值设置li的text和value属性
然后调用DropDownList.Items.Add(li);不知道理解对了没有……

Answer 5

先从数据库取出数据，然后绑定
DropDownList1.DataTextField="name";
DropDownList1.DataValueField="id";
DropDownList1.DataBind()ListItem li = new ListItem("Text","Value");
DropDownList.Items.Add(li);
~~~~~