ASP.NET 动态写入服务器端控件

///<summary>

/// Create textbox list
///</summary>
///<param name="num">textbox list count</param>
private void CreateTextBoxList(int num)
{
HtmlGenericControl div;
HtmlGenericControl span;
TextBox txt;
RegularExpressionValidator rev;

for (int i = 0; i < num; i++)
{
//创建div
div = new HtmlGenericControl();
div.TagName = "div";
div.ID = "divTextBox" + i.ToString();
div.Attributes["class"] = "item2";

//创建span
span = new HtmlGenericControl();
span.ID = "spanTextBox" + i.ToString();
span.InnerHtml = "Url Address" + (i+1).ToString() + ":";

//创建TextBox
txt = new TextBox();
txt.ID = "txt" + i.ToString();
txt.CssClass = "input";

//创建格式验证控件，并且将其关联到对应的TextBox
rev = new RegularExpressionValidator();
rev.ID = "rev" + i.ToString();
rev.ControlToValidate = txt.ID;
rev.Display = ValidatorDisplay.Dynamic;
rev.ValidationGroup = "ShowListContent";
rev.ValidationExpression = @"(http(s)?://)?([\w-]+\.)+[\w-]+(/[\w- ./?%&amp;=]*)?";
rev.ErrorMessage = "Invalid url Address!";

//添加控件到容器
div.Controls.Add(span);
div.Controls.Add(txt);
div.Controls.Add(rev);
divControls.Controls.Add(div);
}
}

protected void Page_Load(object sender, EventArgs e)
{
if (this.IsPostBack)
{
int txtCount = int.Parse(txtTextCount.Text);

// 注意：每次PostBack时，都需要重新动态创建TextBox
CreateTextBoxList(txtCount);
}
}

protected void btnCreate_Click(object sender, EventArgs e)
{
txtTextCount.Enabled = false;
btnCreate.Enabled = false;
}

protected void btnOK_Click(object sender, EventArgs e)
{
TextBox txt;
StringBuilder sbResult = new StringBuilder() ;
int txtCount = int.Parse(txtTextCount.Text);

//遍历获取动态创建的TextBox们中的Text值
for (int i = 0; i < txtCount; i++)
{
//注意：这里必须通过上层容器来获取动态创建的TextBox，才能获取取ViewState内容
txt = divControls.FindControl("txt" + i.ToString()) as TextBox;

if (txt != null && txt.Text.Trim().Length > 0)
{
sbResult.AppendFormat("Url Address{0}: {1}.<br />", i+1, txt.Text.Trim());
}
}

divMessage.InnerHtml = sbResult.ToString();
}