Question

我使用下面的代码动态创建了一些TextBox，并在此TextBox中输入了一些文本。现在我想在将文本添加到数据库时读取此控件的ID。如何通过单击按钮获取此TextBox的ID。

for (int i = 0; i < dv_count; i++)
{
    TextBox txt_box = new TextBox();
    txt_box.Text = "";
    txt_box.ID = "s" + i;
    placeholder1.Controls.Add(txt_box);
}

protected void btn_act_proceed_Click(object sender, EventArgs e)
{
    int count = placeholder1.Controls.Count; //always return 0

    if (count > 0)
    {
        int dv_count = count / 2;

        for (int i = 0; i < dv_count; i++)
        {
            TextBox  lbl_type = (TextBox )placeholder1.FindControl("s" + i);
        }
    }
}

Answer 1

试试这个

在 Aspx 页面

中

<div runat="server" id="plcholder">
</div>
<asp:Button ID="Button1" runat="server" Text="Button" onclick="Button1_Click" />

现在位于代码

之后

protected void Page_Load(object sender, EventArgs e)
{
    populate();
}

public void populate()
{
    for (int i = 0; i < 3; i++)
    {
        TextBox tb = new TextBox();
        tb.ID = "s" + i;
        tb.Text = "Hello" + i;
        plcholder.Controls.Add(tb);
    }
}

protected void Button1_Click(object sender, EventArgs e)
{
    int cont = plcholder.Controls.Count;

    for (int i = 0; i < cont-1; i++)
    {
        TextBox tx = (TextBox)plcholder.FindControl("s" + i);
        Response.Write(tx.Text);
    }
}

Answer 2

postback期间将失去控制权。因此，在preinit上，您需要再次创建控件或者您可以将控件保持在会话中并从回发中恢复。
一个很好的链接http://www.codeproject.com/Articles/3684/Retaining-State-for-Dynamically-Created-Controls-i
http://www.codeproject.com/Articles/502251/How-to-create-controls-dynamically-in-ASP-NET-and

Answer 3

我没有看到你首先在占位符中添加控件。试试这个

for (int i = 0; i < dv_count; i++)
{
    TextBox txt_box = new TextBox();
    txt_box.Text = "";
    txt_box.ID = "s" + i;
    placeholder1.Controls.Add(txt_box);
}

TextBox lbl_type = (TextBox)placeholder1.FindControl("s" + i);

占位符控件计数始终在按钮单击时返回0

3 个答案: