单例模式的窗口对象被close后,对象本身还存在吗?
有一个窗口设计成单例模式,但是点确定按钮时CLOSE此窗口。这时对象本身还存在吗?
我理解的应该是不存在了,但跟踪执行了一下,发现每次GetInstance时,SelFormInstance还是有值的。
请问什么原因?
调用窗口的代码:
SelectForm SelForm = SelectForm.GetInstance();
SelForm.ShowDialog()
/////////////////////////
public class SelectForm : System.Windows.Forms.Form{private static SelectForm SelFormInstance;public static void SelectForm GetInstance(){ if(SelFormInstance == null) { SelFormInstance = new SelectForm (); } return SelFormInstance ;}// 点确定时,窗口被CLOSE了。public void btnOK_Click(object sender, EventArgs e){ this.close();}}
public class SelectForm : System.Windows.Forms.Form{private static SelectForm SelFormInstance;public static void SelectForm GetInstance(){ if(SelFormInstance == null) { SelFormInstance = new SelectForm (); SelFormInstance.Close += onclose; } return SelFormInstance ;} static void onclose(object sender, EventArgs e) { SelFormInstance = null; }// 点确定时,窗口被CLOSE了。public void btnOK_Click(object sender, EventArgs e){ this.close();}}
[解决办法]
this.Dispose();
[解决办法]
Main方法执行完了肯定就释放了.
你所谓的"存在",A窗体CLSOE后B窗体还可以访问么?
你自己试试在A窗体添加一个静态全局变量,看可不可以访问咯.
结论是---静态是首次调用后,便永远存在了(if ...Main.Run ...).