C# try catch代码块不起效果的解决方法

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我是靠谱客的博主直率盼望，最近开发中收集的这篇文章主要介绍C# try catch代码块不起效果的解决方法，觉得挺不错的，现在分享给大家，希望可以做个参考。

概述

我上次编写winform程序时发生了ObjectDisposedException，后来使用了try catch代码块还是没有解决，源代码：

using System.Windows.Forms;
using System;
using System.Drawing;
using System.Drawing.Drawing2D;
class Program
{
/// <summary>
/// 应用程序的主入口点
/// </summary>
[STAThread]
static void Main()
{
Application.Run(new MainForm()); //在这里，视觉样式是默认的样式，以系统的默认样式为基准
}
}
public class MainForm : Form
{
public MainForm()
{
FormPanel fp = new FormPanel(20);
fp.Location = new Point(0, 0);
}
}
public class FormPanel : UserControl
{
public Panel Head = new Panel();
public Label Close_Label = new Label();
public FormPanel(int Head_Height)
{
#region Head
Head.Parent = this;
Head.Dock = DockStyle.Top;
Head.Height = Head_Height;
#endregion Head
Form f1 = new Form();
this.Parent = f1;
#region Close_Label
Close_Label.Parent = Head;
Close_Label.Dock = DockStyle.Right;
Close_Label.AutoSize = true;
Close_Label.Text = "ｘ"; //这里的ｘ不是x，为了美观，输入了全角字符，不要随便使用
Close_Label.MouseClick += (sender, e) =>
{
if (e.Button == MouseButtons.Left)
{
f1.Close();
this.Dispose();
}
}
#endregion
}
}

endregion后面可以添加任何字符，编译后相当于不存在，也就是单行注释，但不能删除，因为有region

加上try catch代码块以后：


using System.Windows.Forms;
using System;
using System.Drawing;
using System.Drawing.Drawing2D;
class Program
{
/// <summary>
/// 应用程序的主入口点
/// </summary>
[STAThread]
static void Main()
{
Application.Run(new MainForm()); //在这里，视觉样式是默认的样式，以系统的默认样式为基准
}
}
public class MainForm : Form
{
public MainForm()
{
FormPanel fp = new FormPanel(20);
fp.Location = new Point(0, 0);
}
}
public class FormPanel : UserControl
{
public Panel Head = new Panel();
public Label Close_Label = new Label();
public FormPanel(int Head_Height)
{
#region Head
Head.Parent = this;
Head.Dock = DockStyle.Top;
Head.Height = Head_Height;
#endregion Head
Form f1 = new Form();
this.Parent = f1;
#region Close_Label
Close_Label.Parent = Head;
Close_Label.Dock = DockStyle.Right;
Close_Label.AutoSize = true;
Close_Label.Text = "ｘ"; //这里的ｘ不是x，为了美观，输入了全角字符，不要随便使用
Close_Label.MouseClick += (sender, e) =>
{
if (e.Button == MouseButtons.Left)
{
try
{
f1.Close();
this.Dispose();
}
catch { }
}
}
#endregion
}
}

原因是：

f1.Close()导致执行了FormPanel.Dispose()，这样try catch代码块不在class外面，解决方法：

public class FormPanel : UserControl
{
public void Close(IsDispose)
{
this.Parent = null;
f1.Close();
if (IsDispose)
this.Dispose();
}
Form f1 = new Form(); //将f1设为全局变量
public Panel Head = new Panel();
public Label Close_Label = new Label();
public FormPanel(int Head_Height, bool CloseIsDispose)
{
#region Head
Head.Parent = this;
Head.Dock = DockStyle.Top;
Head.Height = Head_Height;
#endregion Head
this.Parent = f1;
#region Close_Label
Close_Label.Parent = Head;
Close_Label.Dock = DockStyle.Right;
Close_Label.AutoSize = true;
Close_Label.Text = "ｘ"; //这里的ｘ不是x，为了美观，输入了全角字符，不要随便使用
Close_Label.MouseClick += (sender, e) =>
{
if (e.Button == MouseButtons.Left)
{
this.Close(CloseIsDispose);
}
}
#endregion
}
}

总结：尽量不要手动添加代码关闭这个控件类的父窗体，如要关闭父窗体，请确认Close函数要在所有代码之后，否则设置这个控件类的父容器为null，再关闭父窗体，执行完所有代码之后，清除这个控件类。