Winform程序窗体间的跳转

关于Winform程序窗体间的跳转问题:

对于编程新手来讲,winform程序窗体间的跳转,经常会出现一些异常,或是弹出重复的窗口,如下图

下面给出一种方法,可以很好的避免掉这样的问题:
首先,在主程序Program中,定义一个“找窗体或是创建窗体”的方法,见以下代码:

 1 namespace FormJump
 2 {
 3     static class Program
 4     {
 5         public static List<Form> formList = new List<Form>();
 6         /// <summary>
 7         /// 找窗体或创建窗体的方法
 8         /// </summary>
 9         /// <param name="type"></param>
10         /// <returns></returns>
11         internal static Form FindOrCreateFrom(Type type)
12         {
13             Form form = null;
14             foreach (Form formItem in Program.formList)
15             {
16                 if (formItem.GetType() == type)
17                 {
18                     form = formItem;
19                     form.Activate();
20                     break;
21                 }             
22             }
23             if (form == null)
24             {
25                 object obj = Activator.CreateInstance(type);
26                 if (obj is Form)
27                 {
28                     form = obj as Form;
29                     form.Show();
30                 }
31             }
32             return form;
33         }
34         /// <summary>
35         /// 应用程序的主入口点。
36         /// </summary>
37         [STAThread]
38         static void Main()
39         {
40             Application.EnableVisualStyles();
41             Application.SetCompatibleTextRenderingDefault(false);
42             Application.Run(new FrmMain());
43         }
44     }
45 }

然后添加一个FrmChild的子窗体,编写一个加载和关闭窗体的方法,见以下代码:

 1 namespace FormJump
 2 {
 3     public partial class FrmChild : Form
 4     {
 5         public FrmChild()
 6         {
 7             this.Load += new EventHandler(FrmChild_Load);
 8             this.FormClosed += new FormClosedEventHandler(FrmChild_FormClosed);
 9         }
10         public void FrmChild_Load(object sender, EventArgs e)
11         {
12             Program.formList.Add(this);
13         }
14 
15         public void FrmChild_FormClosed(object sender, FormClosedEventArgs e)
16         {
17             Program.formList.Remove(this);
18         }
19     }
20 }

所有有可能被弹出的窗体都继承FrmChild窗体

1     public partial class Form1 : FrmChild   
2     {
3         public Form1()
4         {
5             InitializeComponent();
6         }
7     }

另外,我们在编写窗体弹出事件的时候,不要再使用一下代码,

 1         /// <summary>
 2         /// 打开Form1窗体
 3         /// </summary>
 4         /// <param name="sender"></param>
 5         /// <param name="e"></param>
 6         private void btnShow1_Click(object sender, EventArgs e)
 7         {
 8             Form1 frm1 = new Form1();
 9             frm1.Show();
10         }

可以直接调用“找窗体或是创建窗体”的方法,所有的窗体弹出都可以调用这样的方法:

 1         /// <summary>
 2         /// 打开Form1窗体
 3         /// </summary>
 4         /// <param name="sender"></param>
 5         /// <param name="e"></param>
 6         private void btnShow1_Click(object sender, EventArgs e)
 7         {
 8             Program.FindOrCreateFrom(typeof(Form1));
 9         }
10 
11         private void btnShow2_Click(object sender, EventArgs e)
12         {
13             Program.FindOrCreateFrom(typeof(Form2));
14         }
15 
16         private void btnShow3_Click(object sender, EventArgs e)
17         {
18             Program.FindOrCreateFrom(typeof(Form3));
19         }

这样,如若窗体已经打开,可以直接显示在最前方,如若还没有弹出,点击则仅会弹出一个窗体!

 

关于MDI窗体的跳转,可以定义一下类似的方法:

        private void FindChildForm(Type type)
        {
            Form frm = null;
            foreach (Form frmChild in this.MdiChildren)
            {
                if (frmChild.GetType() == type)
                {
                    frm = frmChild;
                    frm.Activate();
                    break;
                }
            }
            if (frm==null)
            {
                frm = (Form)Activator.CreateInstance(type);
                frm.MdiParent = this;
                frm.Show();
            }
        }

  

  

posted @ 2012-07-28 15:46  JeffQing  阅读(27598)  评论(0编辑  收藏  举报