摘要： 首先 引用Microsoft.VisualBasic然后新建一个类 single public class single:Microsoft.VisualBasic.ApplicationServices.WindowsFormsApplicationBase { App a; public single() { this.IsSingleInstance = true; } protected override bool OnStartup(Microsoft.VisualBasic.ApplicationServices.StartupEventArgs eventArgs) { a = 阅读全文