摘要:動態產生控制項!?
因為常遇到這種問題,但Google裡的文章又沒有很確實的做法,於是今天做了一個小小的實驗
首先,我們先建立一個網站,然後新增一個webControl控制項,這個控制項主要負責,動態新增N個TextBox
而為了保留值,所以我們必需把code寫在Page_load 或OnInit中,程式碼如下:
using System; using System.Collections.Generic; using System.Linq; using System.Web; using System.Web.UI; 
using System.Web.UI.WebControls; public partial class WebUserControl : System.Web.UI.UserControl { 
private int controlsValue=0; TextBox tb; public int ControlsValue 
{ 
get { return controlsValue; } set { controlsValue = value; } 
} protected override void OnInit(EventArgs e) { for (int i = 0; i < controlsValue; i++) { tb = new TextBox(); tb.ID = "text_" + i.ToString(); tb.Text = i.ToString(); this.Controls.Add(tb); } } protected void Page_Load(object sender, EventArgs e) { } }接下來新增一個WebPage,直接看程式碼:
using System; using System.Web.UI; using System.Web.UI.WebControls; public partial class Default2 : System.Web.UI.Page { Control c; protected void Page_Load(object sender, EventArgs e) { String val = TextBox1.Text; if (val != "") { int tbVal=0; bool rtn = int.TryParse(val, out tbVal); if (rtn) { c = LoadControl("WebUserControl.ascx"); //用Reflection設定WebControl的方法 c.GetType().InvokeMember("ControlsValue", System.Reflection.BindingFlags.SetProperty, null, c, new object[] { tbVal }); PlaceHolder1.Controls.Add(c); } } } protected void Button1_Click(object sender, EventArgs e) { if (PlaceHolder1.HasControls()) Response.Write("控制項還在"); else Response.Write("控制項不在"); } protected void Button2_Click(object sender, EventArgs e) { if (c != null) { PlaceHolder1.Controls.Add(c); } } /// <summary> /// 拿取TextBox所有的值,用逗號分開 /// </summary> /// <param name="sender"></param> /// <param name="e"></param> protected void Button3_Click(object sender, EventArgs e) { string temp = ""; if (c != null) { if (c.HasControls()) { //拿取Control ControlCollection c1 = c.Controls; foreach (Control item in c1) { //判斷控制項為TextBox Control if (item.GetType().ToString() == "System.Web.UI.WebControls.TextBox") { temp += ((TextBox)item).Text + ","; } } } } Label1.Text = temp; } }顯示畫面:
實驗結果:
先輸入控制項數量,按查詢,然後在取值後,可以發現資料存在!