This class provides an interface used to query information about a method including such characteristics as the number and types of arguments, and the return type. Instances of NSMethodSignature are created using NSObject's methodSignature-ForSelector: method.

@interface NSMethodSignature : NSObject
// Instance Methods
- (unsigned)frameLength;
- (const char *)getArgumentTypeAtIndex:(unsigned)index;
- (BOOL)isOneway;
- (unsigned)methodReturnLength;
- (const char *)methodReturnType;
- (unsigned)numberOfArguments;