我有Form和Class: Form1＆amp; Timer
在Form1中，我有一个看起来像这样的按钮
public void browseSoundToolStripMenuItem_Click(object sender, EventArgs e)
{
OpenFileDialog dialog1 = new OpenFileDialog();
dialog1.Title = "Browse to find sound file to play";
dialog1.InitialDirectory = @"c:\";
dialog1.Filter = "Wav Files (*.wav)|*.wav";
dialog1.FilterIndex = 2;
dialog1.RestoreDirectory = true;
//PlaySound(dialog1.FileName, new System.IntPtr(), PlaySoundFlags.SND_SYNC);
}
在Timer.cs中我有Event，如下所示：
public void alert_sound(object source, ElapsedEventArgs e)
{
MessageBox.Show("Alert Sound ding ding ding");
//PlaySound(dialog1.FileName, new System.IntPtr(), Form1.PlaySoundFlags.SND_SYNC);
alert_timer.Stop();
}
问题是在Timer.cs中它表示当前上下文中不存在dialog1。如何将Form1中的对话框1调用到我的Timer课程中？
答案 0 :(得分：2)
您已在browseSoundToolStripMenuItem_Click事件方法的本地scope中创建了dialog1变量。要从不同的事件访问它，您需要在类级别创建它。像这样：
Exception Type: EXC_BAD_ACCESS (SIGSEGV)
Exception Subtype: KERN_INVALID_ADDRESS at 0x00000000
Triggered by Thread: 0
Thread 0 name:
Thread 0 Crashed:
0 CoreFoundation 0x22475196 CFStringHasPrefix + 10 (CFInternal.h:627)
1 CoreText 0x247af94e ___ZL36GetSFTrimCharSetForChineseOrJapanesePPK9TFontInfo_block_invoke + 158 (SplicedFontSupport.cpp:8959)
2 libdispatch.dylib 0x220c180e _dispatch_client_callout + 22 (init.c:819)
3 libdispatch.dylib 0x220d3172 dispatch_once_f$VARIANT$mp + 62 (once.c:60)
4 CoreText 0x24761360 MakeSpliceDescriptor(unsigned long) + 648 (once.h:68)
5 CoreText 0x2474d84e TSplicedFontStashImp::CopySpliceFontAtIndex(long) const + 74 (TDescriptorSource.cpp:3694)
6 CoreText 0x247a9ea0 TSplicedFontStashImp::CopySplicedDescriptorForName(__CFString const*, bool) const + 32 (TDescriptorSource.cpp:3705)
7 CoreText 0x2474cbca TSplicedFontStashImp::CopySplicedDescriptorsForRequest(__CFDictionary const*, unsigned long) const + 134 (TDescriptorSource.cpp:3727)
8 CoreText 0x247a84c4 TDescriptorSource::CopyDescriptorsForRequest(__CFDictionary const*, __CFSet const*, CFComparisonResult (*)(void const*, void const*, void*), void*, unsigned long, TCFRef<__CFArray const*>*) const + 172 (TDescriptorSource.cpp:3630)
9 CoreText 0x2474c0ea TDescriptorSource::CopyDescriptorForRequest(__CFDictionary const*, __CFSet const*, CFComparisonResult (*)(void const*, void const*, void*), void*, unsigned long) const + 86 (TDescriptorSource.cpp:1663)
10 CoreText 0x2474bf1c TDescriptor::CreateMatchingDescriptorInternal(__CFSet const*, bool) const + 424 (TDescriptor.cpp:538)
11 CoreText 0x2474bca8 TDescriptor::InitBaseFont(bool) + 24 (TDescriptor.cpp:642)
12 CoreText 0x2475eaa2 TDescriptor::CreateMatchingDescriptor(__CFSet const*, float, unsigned long) const + 278 (TDescriptor.h:62)
13 CoreText 0x2475e942 CTFontCreateWithFontDescriptor + 34 (CTFont.cpp:93)
14 CoreText 0x2475d85a CTFontCreateUIFontForLanguage + 22 (CTFont.cpp:152)
15 UIFoundation 0x26a7531c +[UIFont systemFontOfSize:traits:] + 360 (UIFont.m:279)
16 UIKit 0x26ad6216 -[UILabel _commonInit] + 86 (UILabel.m:504)
17 UIKit 0x26ad60b0 -[UILabel initWithFrame:] + 76 (UILabel.m:531)
18 UIKit 0x26aeeaf4 -[UIView init] + 44 (UIView.m:2343)
19 UIKit 0x26b6ed28 -[UINavigationItemView initWithNavigationItem:] + 196 (UINavigationBar.m:9834)
20 UIKit 0x26debe9e -[UINavigationItem _defaultTitleView] + 130 (UINavigationBar.m:1469)
21 UIKit 0x26b6ec34 -[UINavigationItem _titleView] + 116 (UINavigationBar.m:1479)
22 UIKit 0x26c094bc -[UINavigationBar _removeItemsFromSuperview:] + 140 (UINavigationBar.m:6931)
23 UIKit 0x26deed7c -[UINavigationBar _setDecodedItems:] + 496 (UINavigationBar.m:2697)
24 UIKit 0x26dee99c -[UINavigationBar initWithCoder:] + 484 (UINavigationBar.m:2662)
25 UIKit 0x2709910e UINibDecoderDecodeObjectForValue + 782 (UINibDecoder.m:705)
26 UIKit 0x27098df4 -[UINibDecoder decodeObjectForKey:] + 296 (UINibDecoder.m:792)
27 UIKit 0x26deaf16 -[UINavigationItem initWithCoder:] + 734 (UINavigationBar.m:548)
28 UIKit 0x2709910e UINibDecoderDecodeObjectForValue + 782 (UINibDecoder.m:705)
29 UIKit 0x27098df4 -[UINibDecoder decodeObjectForKey:] + 296 (UINibDecoder.m:792)
30 UIKit 0x26f814a4 -[UIRuntimeConnection initWithCoder:] + 160 (UIRuntimeConnection.m:23)
31 UIKit 0x2709910e UINibDecoderDecodeObjectForValue + 782 (UINibDecoder.m:705)
32 UIKit 0x270990a0 UINibDecoderDecodeObjectForValue + 672 (UINibDecoder.m:602)
33 UIKit 0x27098df4 -[UINibDecoder decodeObjectForKey:] + 296 (UINibDecoder.m:792)
34 UIKit 0x26f80a0a -[UINib instantiateWithOwner:options:] + 1110 (UINib.m:345)
35 UIKit 0x26e33aa2 -[UIViewController _loadViewFromNibNamed:bundle:] + 322 (UIViewController.m:2309)
36 UIKit 0x26c06ffa -[UIViewController loadView] + 142 (UIViewController.m:2438)
37 UIKit 0x26acca1e -[UIViewController loadViewIfRequired] + 150 (UIViewController.m:2537)
38 UIKit 0x26acc970 -[UIViewController view] + 24 (UIViewController.m:2598)
39 UIKit 0x26ad3638 -[UIWindow addRootViewControllerViewIfPossible] + 68 (UIWindow.m:1445)
40 UIKit 0x26ad0b3c -[UIWindow _setHidden:forced:] + 276 (UIWindow.m:1529)
41 UIKit 0x26b45a5c -[UIWindow makeKeyAndVisible] + 48 (UIWindow.m:4929)
42 Electrical Calculations FREE 0x0008bb68 0x4d000 + 256872
43 UIKit 0x26b41784 -[UIApplication _handleDelegateCallbacksWithOptions:isSuspended:restoreState:] + 392 (UIApplication.m:1865)
44 UIKit 0x26d692d0 -[UIApplication _callInitializationDelegatesForMainScene:transitionContext:] + 3080 (UIApplication.m:2112)
45 UIKit 0x26d6d284 -[UIApplication _runWithMainScene:transitionContext:completion:] + 1588 (UIApplication.m:3355)
46 UIKit 0x26d8183c __84-[UIApplication _handleApplicationActivationWithScene:transitionContext:completion:]_block_invoke3286 + 36 (UIApplication.m:12263)
47 UIKit 0x26d6a7b2 -[UIApplication workspaceDidEndTransaction:] + 134 (UIApplication.m:2748)
48 FrontBoardServices 0x23bf6c06 __FBSSERIALQUEUE_IS_CALLING_OUT_TO_A_BLOCK__ + 18 (FBSSerialQueue.m:158)
49 FrontBoardServices 0x23bf6ab8 -[FBSSerialQueue _performNext] + 224 (FBSSerialQueue.m:177)
50 FrontBoardServices 0x23bf6db8 -[FBSSerialQueue _performNextFromRunLoopSource] + 48 (FBSSerialQueue.m:206)
51 CoreFoundation 0x22515dfe __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 14 (CFRunLoop.c:1761)
52 CoreFoundation 0x225159ec __CFRunLoopDoSources0 + 452 (CFRunLoop.c:1807)
53 CoreFoundation 0x22513d5a __CFRunLoopRun + 794 (CFRunLoop.c:2536)
54 CoreFoundation 0x22463228 CFRunLoopRunSpecific + 520 (CFRunLoop.c:2814)
55 CoreFoundation 0x22463014 CFRunLoopRunInMode + 108 (CFRunLoop.c:2844)
56 UIKit 0x26b3ac3c -[UIApplication _run] + 524 (UIApplication.m:2578)
57 UIKit 0x26b35188 UIApplicationMain + 144 (UIApplication.m:3772)
58 Electrical Calculations FREE 0x00082920 0x4d000 + 219424
59 libdyld.dylib 0x2210b872 start + 2 (start_glue.s:64)
答案 1 :(得分：2)
在您的示例中，需要在模块级别声明dialog1。您在browseSoundToolStripMenuItem_Click（）方法中声明了它，因此dialog1只有该方法的范围。
移动此行：
OpenFileDialog dialog1 = new OpenFileDialog();
到表单的顶部。
答案 2 :(得分：1)
您必须将文件名存储在可由其他方法调用的变量中。
string filename = dialog1.Filename;
可以将filename变量用作类级变量，但这是一个建议，因为我对你的类及其布局一无所知。