#import <Foundation/Foundation.h>
int main(int argc, const char * argv[]) {
char *s = "Hello";
//C - > OC
NSString * str1 = [[NSString alloc] initWithUTF8String:s];
//OC -> C
const char *p1 = [str1 UTF8String];
const char *p2 = [str1 cStringUsingEncoding:NSASCIIStringEncoding];
NSLog(@"%s %s",p1,p2);
// const 声明的字符串不允许改变
return 0;
}