C++ 错误 C2100 - 非法间接
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/16147219/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
Error C2100 - Illegal Indirection
提问by Byron
I have a very simple program written to define a * operator in an array template class. When I try to compile it gives me an error "illegal indirection". Any help on the matter would be greatly appreciated!
我编写了一个非常简单的程序来在数组模板类中定义 * 运算符。当我尝试编译它给我一个错误“非法间接”。对此事的任何帮助将不胜感激！
This is the operator definition:
这是运算符定义：
template <typename T>
NumericArray<T> NumericArray<T>::operator * (const int factor) const
{
NumericArray<T>* TempArray2 = new NumericArray<T>(Size());
for (int i=0; i<Size(); i++)
{
*TempArray2[i] = ((GetElement(i))*(factor));
}
return *TempArray2;
}
And this is the implementation in the test main function:
这是测试主函数中的实现：
cout<<((*intArray1)*5).GetElement(0);
cout<<((*intArray1)*5).GetElement(1);
cout<<((*intArray1)*5).GetElement(2);
Any ideas?
有任何想法吗？
采纳答案by Joseph Mansfield
Don't forget your operator precedencerules. It seems that you want:
不要忘记您的运算符优先级规则。看来你想要：
(*TempArray2)[i]
Otherwise your expression *TempArray2[i]is considered as *(TempArray2[i])and I suppose your NumericArray<T>type doesn't have the unary*operator overloaded.
否则你的表达式*TempArray2[i]被认为是*(TempArray2[i])，我想你的NumericArray<T>类型没有重载一元运算*符。
回答by molbdnilo
In *TempArray2[i], the *is applied to TempArray[2]because of the precedence rules, and there's a fair chance that the array elements don't have a unary *operator.
在 中*TempArray2[i]，由于优先规则，*应用于TempArray[2]，并且数组元素很可能没有一元运算*符。
Butyour use of dynamic allocation and then dereferencing to return by value means that you have a memory leak.
(You don't need newto create objects in C++ - you probably don't need to use it in maineither.)
但是您使用动态分配然后取消引用以按值返回意味着您有内存泄漏。
（您不需要new在 C++ 中创建对象 - 您可能也不需要在main其中使用它。）
This would be better (and avoids the whole indirection issue):
这会更好（并避免整个间接问题）：
template <typename T>
NumericArray<T> NumericArray<T>::operator * (int factor) const
{
NumericArray<T> TempArray(Size());
for (int i = 0; i < Size(); i++)
{
TempArray[i] = GetElement(i) * factor;
}
return TempArray;
}
