asp.net 如何在内容页面初始化的时候获得该内容页面中用户控件中DropDownList选定的值
public partial class Company : System.Web.UI.UserControl
{
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
Bind();
}
}

public void Bind()
{
ClassCom c = new ClassCom();
List<ClassCom> ClassComItems = new List<ClassCom>()
{
new ClassCom{CID=1,CName="小一"},
new ClassCom{CID=2,CName="小二"},
new ClassCom{CID=3,CName="小三"},
new ClassCom{CID=4,CName="小四"}
};

this.DropDownList_Company.DataSource = ClassComItems;
this.DropDownList_Company.DataTextField = "CName";
this.DropDownList_Company.DataValueField = "CID";
this.DropDownList_Company.DataBind();

this.SelectValue = this.DropDownList_Company.SelectedValue;
}

[Category("数据绑定")]
private string _SelectValue;

public string SelectValue
{
get { return _SelectValue; }
set { _SelectValue = value; }
}
}

ASP.NET DropDownList 控件

[解决办法]

protected override void OnPreRender(EventArgs e) {
base.OnPreRender(e);

// your codes.
}

[解决办法]
Refer UserControl related:
http://www.cnblogs.com/insus/tag/UserControl/