Question

我已经创建了一个动态添加控件的表单，用户选择了他想要的控件类型放置在占位符中。现在我想添加一个Image Button Click事件来动态创建Image Button ..我没有成功在过去两天..我尝试过使用委托n事件处理，这对我来说是一个新概念.. 我用它来迭代并分配属性

 <
     void IterateThroughChildren(Control parent)
    {
        foreach (Control c in parent.Controls)
        {
if (c.GetType().ToString().Equals("System.Web.UI.WebControls.ImageButton") &&
               c.ID == null)
            {
                ((ImageButton)c).ImageUrl = @"pictures/close-icon.png";
                ((ImageButton)c).ID = "Imagebtn" +count.ToString();

                ((ImageButton)c).Click += new ImageButtonClickEventHandler(UserControl1_ImageButtonClickEvent);            



            }>

使用此委托和事件处理程序来指定函数

  <public delegate void ImageButtonClickEventHandler(Object sender, EventArgs args);
    public event ImageButtonClickEventHandler ImageButtonClickEvent;

    private void imageButton_Click(object sender, System.EventArgs e)
    {
        if (ImageButtonClickEvent != null)
        {
            ImageButtonClickEvent(sender, e);
        }
    }

    private void UserControl1_ImageButtonClickEvent(Object sender, EventArgs args)
    {
        CreateRadioButtons(sender , args);
    }>

**

我还想知道其他调用函数的方法动态创建conlrols ..

**

预先感谢任何一位助手.. 这是完整的代码..

    <using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

public partial class _Default : System.Web.UI.Page
{
    int count = 1;
    static int m = 0;
    static int n = 0;
    protected void Page_Load(object sender, EventArgs e)
    {
        btnAddControl.Visible = false;
        btnAddText.Visible = false;
    }

    void IterateThroughChildren(Control parent)
    {
        foreach (Control c in parent.Controls)
        {
            if (c.GetType().ToString().Equals("System.Web.UI.WebControls.TextBox") &&
                  c.ID == null)
            {
                ((TextBox)c).ID = "txtQ" + count.ToString();
                ((TextBox)c).Text = "Add Text Here" + count.ToString();
                ((TextBox)c).Columns = 90;
                ((TextBox)c).Focus();
                 //((TextBox)c).TextChanged = "CreateRadioButtons()";
               // ((TextBox)c).Attributes["onclick"] = "this.CreateRadiobuttons()";
                //((TextBox)c).TextChanged();
                    //+= CreateRadioButton;                
                //((TextBox)c).Focus = CreateRadioButtons();

                count++;
            }
            if (c.GetType().ToString().Equals("System.Web.UI.WebControls.RadioButton") &&
               c.ID == null)
            {

            }
            if (c.GetType().ToString().Equals("System.Web.UI.WebControls.ImageButton") &&
               c.ID == null)
            {
                ((ImageButton)c).ImageUrl = @"pictures/close-icon.png";
                ((ImageButton)c).ID = "Imagebtn" +count.ToString();
                ((ImageButton)c).Click += new ImageClickEventHandler(_Default_Click);
                ((ImageButton)c).Click += new ImageClickEventHandler(CreateRadioButtons);

            }
            if (c.GetType().ToString().Equals("System.Web.UI.WebControls.Label") &&
                 c.ID == null)
            {
                ((Label)c).Text = count.ToString() + ".";
            }

            if (c.Controls.Count > 0)
            {
                IterateThroughChildren(c);
            }
        }
    }

    void _Default_Click(object sender, ImageClickEventArgs e)
    {
        CreateRadioButtons(sender,e);
        throw new NotImplementedException();
    }

    protected void abc_acb( object sender, EventArgs e)
    { 
    }

    protected void CreateRadioButtons(object sender, EventArgs e)
    {
        if (Page.IsPostBack == true)
        {
            btnAddControl.Visible = true;
            m++;

            // now, create n TextBoxes, adding them to the PlaceHolder TextBoxesHere
            for (int i = 0; i < m; i++)
            {

                PlaceHolder1.Controls.Add(new RadioButton());
                PlaceHolder1.Controls.Add(new TextBox());
                PlaceHolder1.Controls.Add(new ImageButton());
                LiteralControl literalBreak3 = new LiteralControl("<br />");
                PlaceHolder1.Controls.Add(literalBreak3);
                LiteralControl literalBreak = new LiteralControl("<br />");
                PlaceHolder1.Controls.Add(literalBreak);
                LiteralControl literalBreak2 = new LiteralControl("<br />");
                PlaceHolder1.Controls.Add(literalBreak2);
            }
            EventHandler eh = new EventHandler(CreateRadioButtons);
            TextBox Mytextbox = new TextBox();
            Mytextbox.ID = "123";
            Mytextbox.Columns = 90;
            Mytextbox.AutoPostBack = true;
            Mytextbox.Text = "Click to create another option";
            Mytextbox.TextChanged += eh;
            //Mytextbox.TextChanged += CreateRadioButtons;
            PlaceHolder1.Controls.Add(new RadioButton());
            PlaceHolder1.Controls.Add(Mytextbox);
            LiteralControl literalBreak4 = new LiteralControl("<br />");
            PlaceHolder1.Controls.Add(literalBreak4);
            LiteralControl literalBreak5 = new LiteralControl("<br />");
            PlaceHolder1.Controls.Add(literalBreak5);

            // now, set the Text property of each TextBox
            IterateThroughChildren(this);
        }

    }
    protected void CreateTextBoxes(object sender , EventArgs e)
    {
        btnAddText.Visible = true;


        if (Page.IsPostBack == true)
        {
            n++;

            // now, create n TextBoxes, adding them to the PlaceHolder TextBoxesHere
            for (int i = 0; i < n; i++)
            {
                TextBoxesHere.Controls.Add(new Label());                
                TextBoxesHere.Controls.Add(new TextBox());
                TextBoxesHere.Controls.Add(new ImageButton()); 
                LiteralControl literalBreak = new LiteralControl("<br />");
                TextBoxesHere.Controls.Add(literalBreak);
                LiteralControl literalBreak1 = new LiteralControl("<br />");
                TextBoxesHere.Controls.Add(literalBreak1);

            }

            // now, set the Text property of each TextBox
            IterateThroughChildren(this);
        }

    }


    protected void ddlSelectControl_SelectedIndexChanged(object sender, EventArgs e)
    {

        string a = ddlSelectControl.SelectedValue.ToString();
        if (a == "0")
        {
            CreateRadioButtons(sender, e);
        }
        else
        {
            CreateTextBoxes(sender ,e);

        }

    }

}
>

Answer 1

目前尚不清楚实际发生了什么，但您的订阅代码会更好（假设.NET 3.5，因此您可以使用LINQ）：

foreach (ImageButton button in parent.Controls
                                     .OfType<ImageButton>()
                                     .Where(c => c.ID == null))
{
    button.ImageUrl = @"pictures/close-icon.png";
    buttonID = "Imagebtn" + count;

    button.Click += new UserControl1_ImageButtonClickEvent;
}

请注意，这只会在parent下迭代控件直接。如果有其他容器控件，您可能需要通过这些控件递归，例如

foreach (CompositeControl container in parent.Controls
                                             .OfType<CompositeControl>())
{
    IterateThroughChildren(container);
}

这可能是实际上错的......但你还没有说出你实际观察到的事情，这会让你更难帮助......

Answer 2

在CreateTextBoxes()

   for (int i = 0; i < n; i++)
   {
             ImageButton iM = new ImageButton();//
             TextBoxesHere.Controls.Add(new Label());
             TextBoxesHere.Controls.Add(new TextBox());                 
             TextBoxesHere.Controls.Add(iM );                           
             LiteralControl literalBreak = new LiteralControl("<br />");                 
             TextBoxesHere.Controls.Add(literalBreak);                 
             LiteralControl literalBreak1 = new LiteralControl("<br />");                 
             TextBoxesHere.Controls.Add(literalBreak1);              
 }

在CreateRadioButtons()

for (int i = 0; i < m; i++)                      
{  
            ImageButton iM = new ImageButton();//
            PlaceHolder1.Controls.Add(iM);                          
            PlaceHolder1.Controls.Add(new TextBox()); 
            PlaceHolder1.Controls.Add(new ImageButton()); 
            LiteralControl literalBreak3 = new LiteralControl("<br />");
            PlaceHolder1.Controls.Add(literalBreak3);                          
            LiteralControl literalBreak = new LiteralControl("<br />");
            PlaceHolder1.Controls.Add(literalBreak);                          
            LiteralControl literalBreak2 = new LiteralControl("<br />");
            PlaceHolder1.Controls.Add(literalBreak2);                      
}

在省略c.ID == null和((ImageButton)c).ID = "Imagebtn" +count.ToString();后，您可以尝试上述代码吗？这就是我想尝试的内容。

Answer 3

让图像按钮在点击上工作的解决方案是这个..

}
protected void img_Click(object sender, ImageClickEventArgs e)
{
    ClientScript.RegisterClientScriptBlock(this.GetType(), "img",
    "<script type = 'text/javascript'>alert('ImageButton Clicked');</script>");
}>

但是在我的情况下，我在CreateRadiobutton中创建按钮，所以点击页面加载函数被调用，因此该属性需要其他解决方案..

如何调用C Sharp上动态创建的图像按钮单击方法？

3 个答案: