#import <Foundation/Foundation.h>
int main(int argc, const char * argv[]) {
@autoreleasepool {
/*float num=24;
NSString *str=[NSString stringWithFormat:@"%f",num];
NSLog(@"%@",str);*/
/* NSString *str1=@"3.14";
float num = [str1 floatValue];
NSLog(@"%.2f",num);*/
/*NSString *str2=@"HelloWorld";
NSLog(@"大写转换%@",[str2 uppercaseString]);
NSLog(@"小写转换%@",[str2 lowercaseString]);
NSLog(@"首字母大写%@",[str2 capitalizedString
]);*/
//oc转化成c语言
NSString *str3=@"http://localhost:8099/test/user=admin&pwd=123";
NSLog(@"%@",str3);
const char *str4 = [str3 UTF8String];
NSLog(@"%s",str4);
}
return 0;
}
原文：http://www.cnblogs.com/jidezhi/p/5120709.html