public static string RangerUsControl(string controlName) { StringBuilder build = new StringBuilder(); HtmlTextWriter htmlWriter = new HtmlTextWriter(new StringWriter(build)); UserControl uc = new UserControl(); Control ctrl=uc.LoadControl(controlName+".ascx");//加载用户定义控件 TextBox txtBox1 = ctrl.FindControl("TextBox1") as TextBox;//获得id为“TextBox1”的控件 txtBox1.Text = "测试"; //给控件初始化 string result; try { ctrl.RenderControl(htmlWriter); } catch { } finally { htmlWriter.Flush(); result=build.ToString(); } return result;//返回控件的HTML代码 } htmlWriter.Flush();