主题：程序重复打开请教

可以用下面代码实现

全局代码：

Public mu As System.Threading.Mutex

BeforeOpenProject事件:

Dim sucess As Boolean = False
mu = new System.Threading.Mutex(True, "dsdfhdfghf", sucess)
If not sucess Then
    MessageBox.Show("只能打开一次!")
    e.Cancel = True
End If