NSString:与char的转换

好记性不如烂笔头，记录下来以便下次使用时查看

• NSString转化为char*

1. 使用cStringUsingEncoding:

 NSString *ocString = @"123456";  
 char* cSring = (char*) [ocString cStringUsingEncoding:NSUTF8StringEncoding];

2. 使用UTF8String:

 NSString *ocString = @"123456";  
 char* cString = (char*) [ocString UTF8String];

• char*转化为NSString

1. 使用initWithCString：

char *cString = "123456"
NSString *ocString = [[NSString alloc] initWithCString: cString encoding:NSASCIIStringEncoding];

2. 使用stringWithFormat：

char *cString = "123456";
NSString *ocString = [NSString stringWithFormat:@"%c", cString];

3. 使用stringWithCString:

char *cString = "123456";
NSString * ocString = [NSString stringWithCString: cString encoding:NSUTF8StringEncoding];