asp.net技术小结（第一条）

 （1）cs：

public string SayHello()//返回类型是string  {

            return "大家好"+DateTime.Now.ToString();

  }

  protected void ShowType()//返回类型是void

        {

            Response.Write(this.GetType() + "<br/>");

            Response.Write(this.GetType().Assembly.Location + "<br/>");

            Response.Write(this.GetType().BaseType + "<br/>");

            Response.Write(this.GetType().BaseType.Assembly.Location + "<br/>");

        }

?

前台调用方法：?

? <%=SayHello() %>

 <% ShowType(); %>

（2）在前台html中写c#代码??

   <%

          for(int i=0;i<10;i++)

{

    Response.Write(i+"</br>");

}

 %>

（3）button弹出确认对话框

OnClientClick="return confirm(‘确定提交吗？‘)"

（4）dropdownlist绑定方法

前台：

     <asp:DropDownList ID="ddlProvince" runat="server" AutoPostBack="True"
            onselectedindexchanged="ddlProvince_SelectedIndexChanged">
            <asp:ListItem Value="hb">河北</asp:ListItem>
            <asp:ListItem Value="sd">山东</asp:ListItem>
            <asp:ListItem Value="hn">河南</asp:ListItem>
        </asp:DropDownList>
        <asp:DropDownList ID="ddlCity" runat="server">

 SqlConnection conn = new SqlConnection();
        conn.ConnectionString = "Data Source=localhost;Initial Catalog=wang;Persist Security Info=True;User ID=sa;Password=24680";
        conn.Open();
        string cmd = "select * from test";
        //建立数据适配器、Table表 然后填充
         SqlDataAdapter da = new SqlDataAdapter(cmd, conn);
        DataTable dt = new DataTable();
         da.Fill(dt);
          ddl.DataSource = dt;
        //  DataSet ds = new DataSet();
        // da.Fill(ds);
        //   ddl.DataSource = ds.Tables[0];         
        ddl.DataTextField = "UserName";
        ddl.DataValueField = "UserAge";
        ddl.DataBind();
        conn.Close();
        ddl.Dispose();

当事件改变时：

 if (ddlProvince.SelectedValue == "hb")
            {
                ddlCity.Items.Clear();
                ddlCity.Items.Add("石家庄");
                ddlCity.Items.Add("唐山");
                ddlCity.Items.Add("保定");
            }

?