【发布时间】：2011-10-23 16:56:14
【问题描述】：
我有一个特定的异常类，我想从类方法中抛出并从 main() 函数中的调用代码中捕获。
但是，当我运行它时，我收到以下错误：
Unhandled exception at 0x775915ee in OpenHashTable.exe: 0xC0000005: Access violation. 好像它没有被处理。我不明白为什么会这样。以下是相关代码：
main() {
......
case 'i':
{
cout << "Enter the positive integer you wish to insert: ";
//Input Validation.
if (!(cin >> number))
{
cout << "Please enter a valid positive integer...\n\n";
cin.clear();
cin.ignore(numeric_limits<streamsize>::max(), '\n'); //Taken from http://stackoverflow.com/questions/2075898/good-input-validation-loop-using-cin-c
break;
}
try
{
hashTable.add(abs(number)); //Add positive only integer
}
catch (FullTableException& fte)
{
cout << "HashTable is full!" << endl;
break;
}
catch (DuplicateElementException& dee) //NOT BEING CAUGHT?
{
cout << "HashTable already contains that element." << endl;
break;
}
cout << abs(number) << " added!\n\n";
break;
}
.......
}
这是 HashTable::add() 方法中抛出的异常
//Adds an element into the appropriate index
bool OpenHashTable::add(int toAdd) throw(FullTableException, DuplicateElementException)
{
int index = hash(toAdd);
//Check for duplicate
if (search(toAdd))
throw DuplicateElementException(); //NOT ACTUALLY THROWING??
if (arr[index] != 0) //If element is occupied //GET AN ACCESS VIOLATION HERE
{
int j = 0;
//Linear Probing...
for ( unsigned int i = index + 1; j < 100; i = ((i+1) % 100) )
{
if (arr[i] != 0 && arr[i] != -1) //If element is occupied
{
j++; //Keep count of how many tries, for full array
continue;
}
else
{
arr[i] = toAdd; //Add to array
size++; //Increment size
break;
}
}
if (j == 100) //We've checked all possible elements
throw FullTableException(); //No spaces
}
else
{
arr[index] = toAdd; //Add to array straight away
size++; //Increment size
}
return true; //Successfully added
}
编辑：search() 方法：
bool OpenHashTable::search(int toSearch)
{
int index = hash(toSearch);
if (arr[index] == toSearch)
return true; //Found at index
else
{
int j = 0;
//Linear search for value
for ( unsigned int i = index + 1; j < 100; i = ((i+1) % 100) )
{
if (arr[i] == toSearch)
return true; //found
else if (arr[i] == 0)
return false; //Not in HashTable
else
continue; //Probe next element
}
if (j == 100)
return false; //Not in HashTable
}
return true;
}
编辑：_尝试..._except() 调用堆栈：
ntdll.dll!775915ee()
[Frames below may be incorrect and/or missing, no symbols loaded for ntdll.dll]
ntdll.dll!775915ee()
ntdll.dll!7761852f()
ntdll.dll!776372ec()
ntdll.dll!7760063e()
ntdll.dll!775fabf9()
ntdll.dll!77580143()
KernelBase.dll!75c5b9bc()
KernelBase.dll!75c5b9bc()
KernelBase.dll!75c5b9bc()
msvcr100d.dll!_CxxThrowException(void * pExceptionObject, const _s__ThrowInfo * pThrowInfo) Line 157 C++
OpenHashTable.exe!OpenHashTable::add(int toAdd) Line 100 //THIS IS "throw DuplicateElementException()"
OpenHashTable.exe!main() Line 267 //THIS IS "hashTable.add(abs(number));"
编辑：重复元素异常：
//Just an empty class
class DuplicateElementException : public exception
{
private:
public:
DuplicateElementException(); //Constructor
~DuplicateElementException(); //Destructor
};
//empty constructor and destructor definitions...
非常感谢任何帮助。
谢谢
卡鲁姆
【问题讨论】：
-
您的搜索方法是什么？另外，您不应该根据表大小来修改哈希值吗？
-
已添加。不明白你的意思。哈希函数就是
value % 100（100 是表大小） -
请发
DuplicateElementException的内容 -
当用户输入非数字（如f）时代码中存在错误
-
当键不在表中时，您的搜索是一个无限循环
标签： c++ oop exception exception-handling try-catch