启用动态文本框以检查c＃中的动态复选框

Question

Here i am creating a textbox and its corresponding checkbox. what i need is... i want to enable the textbox when i check the checkbox Note: textbox is initially disabled

    for (int i = 0; i < count; i++)
    {
        TableRow row = new TableRow();
        for (int j = 0; j < 1; j++)
        {
            TableCell cell = new TableCell();
            CheckBox chk = new CheckBox();
            TextBox txt_ele = new TextBox();

            txt_ele.ID = "elective" + i;
            txt_ele.Enabled = false;

            chk.ID = "chk_" + i.ToString();
            chk.Text = "Has Elective Subjects";
            chk.AutoPostBack = true;

            cell.Controls.Add(chk);
            cell.Controls.Add(txt_ele);

            row.Cells.Add(cell);
            chk.CheckedChanged += new System.EventHandler (chkDynamic_CheckedChanged);
        }
        table.Rows.Add(row);
        this.NumberOfControls++;
    }

page.Form.Controls.Add(table);

and check box checked event is as follows

protected void chkDynamic_CheckedChanged (object sender, EventArgs e)
{
    CheckBox lb = (CheckBox)sender;
    if (lb.Checked)
    {
          //how to do here
    }
}

Answer 1

How about:

protected void chkDynamic_CheckedChanged (object sender, EventArgs e)
{
    CheckBox lb = (CheckBox)sender;
    if (lb.Checked)
    {
        (Page.FindControlRecursive(
            "elective" + System.Text.RegularExpressions.Regex.Match(
                lb.ID, 
                @"(\d+)(?!.*\d)").ToString()) 
            as System.Web.UI.WebControls.WebControl)
        .Enabled = true;
    }
}

public static Control FindControlRecursive(this Control Root, string Id)
{
    if (Root.ID == Id)
    {
        return Root;
    }

    foreach (Control Ctl in Root.Controls)
    {
        Control FoundCtl = FindControlRecursive(Ctl, Id);
        if (FoundCtl != null)
        {
            return FoundCtl;
        }
    }

    return null;
}

This is matching the numeric part of the checkbox id and then using it to create the textbox id. Using FindControl to retrieve the control and then enabling it.

Answer 2

对于动态（没有回发），你需要在你的aspx页面或jQuery上使用AJAX（UpdatePanel），至少它更容易

Answer 3

this is a very dirty solution but its for you to pick it up and make it a production solution:

protected void chkDynamic_CheckedChanged(object sender, EventArgs e)
{
    CheckBox lb = (CheckBox)sender;
    if (lb.Checked)
    {
        ((TextBox)lb.Parent.FindControl("elective" + lb.ID.Replace("chk_", string.Empty))).Enabled = true;
    }
}