学步园

1、去前后空格：

NSString* str = @" [zhang] 
=  [yu]   ss "; 

NSString* res = [str stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceCharacterSet]];  

2、NSString   字节的长度   UTF8/可改GBK

NSString *str = [NSString stringWithString:@"字节的长度abc"];
NSStringEncoding enc = CFStringConvertEncodingToNSStringEncoding(kCFStringEncodingUTF8);
NSLog(@”%@ length is: %d”,str,[str lengthOfBytesUsingEncoding:enc]);