我得到了这个例外:
NullReferenceException
Object reference not set to an instance of an object
at Namespace.TheClass.TheMethod()
at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
at System.Threading.ExecutionContext.runTryCode(Object userData)
at System.Runtime.CompilerServices.RuntimeHelpers.ExecuteCodeWithGuaranteedCleanup(TryCode code, CleanupCode backoutCode, Object userData)
at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state)
at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean ignoreSyncCtx)
at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
at System.Threading.ThreadHelper.ThreadStart()
在此代码中:
public class TheClass : TheBaseClass
{
protected IList1 List;
public object Object1;
public ManualResetEvent MrEvent = new ManualResetEvent(false);
readonly Attr1 Attr1;
readonly Attr2 Attr2;
readonly EventHandler<Class1> BeginHandler, EndHandler;
readonly EventHandler<Class2> Handler2;
readonly EventHandler<Class3> Handler3;
public TheClass(Attr1 attr1, Attr2 attr2, EventHandler<Class1> beginHandler, EventHandler<Class1> endHandler, EventHandler<Class2> handler2, EventHandler<Class3> handler3)
{
this.Attr1 = attr1;
this.Attr2 = attr2;
this.BeginHandler = beginHandler;
this.EndHandler = endHandler;
this.Handler2 = handler2;
this.Handler3 = handler3;
Thread t = new Thread(Run);
t.IsBackground = true;
t.Start();
}
void TheMethod()
{
Args1 args1 = new Args1();
if (BeginHandler != null)
{
try
{
BeginHandler(this, args1);
}
catch { }
}
try
{
List = GetList(args1);
}
catch { }
if (List != null)
{
List.Event1 += new EventHandler<Args2>(List_Event1);
}
if (Handler3 != null)
{
try
{
Args3 args3 = new Args3(args1.Attr1, args1.Attr2);
Handler3(this, args3);
this.Object1 = args3.Object1;
}
catch { }
}
if (this.Object1 == null)
{
if (args1.Attr1 != null)
try
{
this.Object1 = Class4.GetObject(args1.Attr1);
}
catch { }
}
MrEvent.Set();
Method1();
Method2();
if (List != null)
{
List.Event1 -= new EventHandler<Args2>(List_Event1);
}
if (EndHandler != null)
{
try
{
EndHandler(this, args1);
}
catch { }
}
}
}
我没有看到任何可以抛出提到的句柄null异常的地方。你看到有人吗?
To Veer:你怎么能这么多地改变我的问题的含义? 对那些批准它的人:你怎么能同意它?
答案 0 :(得分:1)
在这段代码中,在try catch块中你不会得到null异常,因为catch块是空的,所以,Exception不会抛出一边,检查其他对象。
答案 1 :(得分:1)
可以从内联方法抛出NullReferenceException。查看Method1和Method2。