加载用户控件传递值的问题

Question

我把代码全部帖上来吧.请高手帮帮忙
这个是.aspx页面:
    private int num = 2;
    protected void Page_Load(object sender, EventArgs e)
    {
        if (!this.IsPostBack)
        {
            SqlConnection con = database.returncon();
            int i = 0;
            SqlCommand cmd1 = new SqlCommand(System.Configuration.ConfigurationManager.AppSettings["DownLoad"], con);
            SqlDataReader sda1 = cmd1.ExecuteReader();
            TableRow tr = new TableRow();
            while (sda1.Read())
            {
                i += 1;
                TableCell td = new TableCell();                DownLoadControl DC = (DownLoadControl)LoadControl("DownLoadControl.ascx");
                DC.D_ID = sda1.GetInt32(0);
                td.Controls.Add(DC);
                tr.Controls.Add(td);
                if (i % num == 0)
                {
                    this.TabShow.Rows.Add(tr);
                    tr = new TableRow();
                }
            }
            if (i % num != 0)
            {
                this.TabShow.Rows.Add(tr);
            }
            sda1.Close();
            con.Close();
        }
    }
这是.ascx页面:
    private int d_id;
    public int D_ID
    {
        get { return this.d_id; }
        set { this.d_id = value; }
    }
    protected void Page_Load(object sender, EventArgs e)
    {
        if (!this.IsPostBack)
        {
            DownLoad Down = new DownLoad();
            SqlConnection con = database.returncon();// 
            SqlCommand cmd = new SqlCommand("select * from DownLoad where ID='" + d_id + "'", con);
            SqlDataReader sda = cmd.ExecuteReader();
            if(sda.Read())
            {
                this.lbl_name.Text = sda.GetString(1);
                this.lbl_D_size.Text = sda.GetString(2);
                this.lbl_D_Update_Time.Text = sda.GetDateTime(3).ToLongDateString();
                this.lbl_D_language.Text = sda.GetString(5);
                this.lbl_D_Nature.Text = sda.GetString(8);
                this.lbl_D_type.Text = sda.GetString(6);
                this.lbl_D_Win.Text = sda.GetString(7);
                this.lbl_D_Coutext.Text = sda.GetString(11);
                this.HL_D_Address.NavigateUrl = sda.GetString(12);
                this.I_Image.ImageUrl = sda.GetString(9);
            }
            sda.Close();
            con.Close();
        }
    }
本人不才,不会写出好的设计模式代码来.两个页面并没有设置缓存,也没有同名.
代码运行调试时出错,下面这一样.
                DownLoadControl DC = (DownLoadControl)LoadControl("DownLoadControl.ascx");
错误:无法将类型为“DownLoadControl”的对象强制转换为类型“DownLoadControl”。也试过这样写: asp.DownLoadControl DC = (asp.DownLoadControl)LoadControl("DownLoadControl.ascx");
         或: Control DC = (Control)LoadControl("DownLoadControl.ascx");
我想得到的效果是:动态加载控件,并传递值给控件的属性.明白吗?
在.aspx页面是动态创建的table

Answer 1

只能用Control类型，不能强制转换
Control   control   =   LoadControl( "路径 ");

Answer 2

Control  control  =  (Control)LoadControl("DownLoadControl.ascx"); 

Answer 3

Control  control  =  LoadControl( "路径 ");
这样的话,control就是Control类型了.不是一样要将control转换成DownLoadControl类型才能对DownLoadControl里的属性赋值.

Answer 4

我在VS2005下面是这样动态创建的，经测试可以，希望没有误解楼主的意思。                DownLoadControl DC = new DownLoadControl();
                DC.D_ID = sda1.GetInt32(0); 
                td.Controls.Add(DC); 
                tr.Controls.Add(td); 
                if (i % num == 0) 
                { 
                    this.TabShow.Rows.Add(tr); 
                    tr = new TableRow(); 
                } 

Answer 5

你测试可以吗?我测试不行啊.
在控件的页面提示错误:this.lbl_name.Text = sda.GetString(1); 未将对象引用设置到对象的实例

Answer 6

用反射试试:protected void Page_Load(object sender, EventArgs e)
    {
        if (!this.IsPostBack)
        {
            SqlConnection con = database.returncon();
            int i = 0;
            SqlCommand cmd1 = new SqlCommand(System.Configuration.ConfigurationManager.AppSettings["DownLoad"], con);
            SqlDataReader sda1 = cmd1.ExecuteReader();
            TableRow tr = new TableRow();
            while (sda1.Read())
            {
                i += 1;
                TableCell td = new TableCell();                Control c = this.LoadControl("DownLoadControl.ascx");
                PropertyInfo pi = c.GetType().GetProperty("D_ID",typeof(int));
                if(pi != null)
                     pi.SetValue(c,sda.GetInt32(0),null);
                td.Controls.Add(DC);
                tr.Controls.Add(td);
                if (i % num == 0)
                {
                    this.TabShow.Rows.Add(tr);
                    tr = new TableRow();
                }
            }
            if (i % num != 0)
            {
                this.TabShow.Rows.Add(tr);
            }
            sda1.Close();
            con.Close();
        }
    } 

Answer 7

向ojlovecd高手致敬,其实我也想过用反射,但是我不熟用Reflection这个,所以就没考虑它了,这个问题害了我两天了.
爱死你了ojlovecd........