infopath 中confirm询问对话框的用法

语法：
expression.Confirm(prompt As String, buttons As XdConfirmButtons) As XdConfirmChoice
实例：
if(XDocument.UI.Confirm("是否保存？",4) == 6)
{
    XDocument.UI.Alert("yes");
}
else
{
    XDocument.UI.Alert("no");
}
枚举：
XdConfirmButtons 显示按钮

Name Value Description
xdOKCancel  1 OK and Cancel buttons are displayed.
xdYesNoCancel  3 Yes, No, and Cancel buttons are displayed.
xdYesNo  4 Yes and No buttons are displayed

XdConfirmChoice  结果

Name Value Description
xdOK  1 The OK button was clicked.
xdCancel  2 The Cancel button was clicked.
xdYes  6 The Yes button was clicked.
xdNo  7 The No button was clicked.