Difference between 'using' and '#using' directive?
According to MSDN is:
The using directive has two uses:
1)To allow the use of types in a namespace so that you do not have to qualify the use of a type in that namespace:
using System.Text;
2)To create an alias for a namespace or a type. This is called a using alias directive.
using Project = PC.MyCompany.Project;
Edit1:
When we say #using<mscorlib.dll>
what does it do?
Is #using
directive specific to C++/CLI ?
What is the basic difference between using
and #us开发者_开发技巧ing
?
The #using directive is C++. Basically it
Imports metadata into a program compiled with /clr.
It is is used to import Microsoft intermediate language (MSIL) file for its managed data and managed constructs.
mscorlib.dll is automatically referenced when compiling with /clr.
Source: http://msdn.microsoft.com/en-us/library/yab9swk4(v=VS.100).aspx
using
on the other hand is applicable to both C++ and C# and you have defined its uses already. In C++:
using namespace System::Reflection;
Also:
#include <iostream>
int main() {
std::cout << "Hello ";
using namespace std;
cout << "World." << endl;
}
#using
is only used in C++ and includes another file to the one it's contained in.
using
is specific to C# and allows you to use classes from the namespace it specifies.
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