父窗口代码：
<scritp type="text/javascript">
function showChil() {
window.showModelDialog("childre.aspx?pare=nn",window,"help:no;");
window.location.href.reload();
}
</script>
<asp:Button id='btn' text="子窗体" runat="server" onclick="showChil()"></asp:Button>
<asp:TextBox id='AllName' runat="server" /> //接受子窗口传来的值
chldre.aspx子窗口代码：
<asp:Button id="btnShow" runat="server" onclick="btnShow_click" />
<asp:TextBox id='txtName' runat="server" />
在.cs代码中
click代码事件中
string names= this.txtName.Text;
Response.Write("<script language='javascript'> opener.document.form1.AllName.value = '" + names + "' ;</script>"); //form1是父窗口中的form表单，AllName是父窗口中的接收文本框
Response.Write("<script language='javascript'>window.close();</script>") ;