C ++：如何将十六进制的HANDLE转换为十进制？

Question

In c++, I get an HANDLE type ID from another function, which appears to be a hexidecimal, and I want to convert it to decimal.

HANDLE id = getCurrentID();
int decimalID = static_cast<int>( id );

But the second line gives out this error:

Cannot convert from 'HANDLE' to 'int'.

This is the first time I encountered HANDLE type. Could someone help and explain? Thank you.

Update:

I am using Windows XP and Visual Studio 2010.

Answer 1

A HANDLE on Windows is a void pointer.
To make an int ( unsigned long etc.) out of it, you cannot use static_cast ,
you´ll need an reinterpret_cast .

But, any int type is neither hexadecimal nor decimal, just a number
which can be expressed in both ways...

Answer 2

I am going to guess that you are on Windows because HANDLE is a name that is usually used by Microsoft's stuff.

The HANDLE type is a pointer to an object (of unspecified type), and is passed into other functions to perform operations on that object. In general, there is not a need to manipulate it directly.

I am not sure exactly why you want to convert it to an int , because it is not usually useful to look at, but you can use a C-style cast to do it, or reinterpret_cast as mentioned in the other answer.

If you want to learn the true types behind these Microsoft type names, you can check out their documentation .

Answer 3

HANDLE基本上是void *，即指针类型，如果需要，可以将HANDLE转换为void *然后转换为int