2017-5-9 An instance operation that opens a unique form

usingSystem;usingSystem.Collections.Generic;usingSystem.ComponentModel;usingSystem.Data;usingSystem.Drawing;usingSystem.Linq;usingSystem.Text;usingSystem.Threading.Tasks;usingSystem.Windows.Forms;namespaceOpen unique Form { Public Partial classForm1:form { PublicForm1 () {InitializeComponent (); } List<Form> flist =NewList<form>(); Private voidButton1_Click (Objectsender, EventArgs e) {            BOOLhas =false; Form2 F2=NewForm2 ( This); foreach(Form Finchflist) {                if(f isForm2) { has=true; F2= f asForm2; }            }            if(has) {F2. WindowState=Formwindowstate.normal; //Focus intoF2.            Focus (); }            Else{flist.                ADD (F2); F2.            Show (); }        }         Public voidDeleteform (Form f) {flist.        Remove (f); }    }}

usingSystem;usingSystem.Collections.Generic;usingSystem.ComponentModel;usingSystem.Data;usingSystem.Drawing;usingSystem.Linq;usingSystem.Text;usingSystem.Threading.Tasks;usingSystem.Windows.Forms;namespaceOpen unique Form { Public Partial classform2:form {Form1 F1=NULL;  PublicForm2 (Form1 F1) {InitializeComponent (); F1=F1; }        Private voidForm2_formclosing (Objectsender, FormClosingEventArgs e) {F1.deleteform ( This); }    }}

2017-5-9 An instance operation that opens a unique form