[Xcode NSString]各種常用轉換函式
在撰寫程式的時候,常常因為語法或是功能所需,要將字串多種類的轉換。在 Objective-C 中,String 屬於一種物件,所以可以隨時作轉換。下面是常用的轉換方式。NSString 轉換為 intNSString *string = @"123";int value = [string intValue];int 轉換為NSStringint value = 123;NSString *string = [NSString stringWithFormat:@"%d", value];NSString 轉換為 NSDateNSString *dateString = @"2014-11-20";NSDateFormatter *dateFormat = [[NSDateFormatter alloc] init];[dateFormat setDateFormat:@"yyyy-MM-dd"];NSDate *date = [dateFormat dateFromString:dateString];NSDate 轉換為NSStringNSDate *today = [NSDate date];NSDateFormatter *dateFormat = [[NSDateFormatter alloc] init];[dateFormat setDateFormat:@"yyyy-MM-dd"];NSString *dateString = [dateFormat stringFromDate:today];NSString 轉換為NSURLNSString *address = @"https://www.google.com.tw";NSURL *url = [NSURL URLWithString:address];NSURL轉換為 NSString//url is NSURLNSString *address= [url absoluteString];NSString 轉換為NSDataNSString *string = @"Hello World";NSData *data = [string dataUsingEncoding:NSUTF8StringEncoding];NSData轉換為 NSString//data is NSDataNSString *string = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];NSString 合併NSString *string1 = @"Hello";NSString *string2 = @"Hello";NSString *string3 = [NSString stringWithFormat:@"%@ %@", string1, string2];NSString 分割NSString *string = @"abc,def,ght";NSArray *array = [string componentsSeparatedByString:@","];// array[0] = "abc"// array[1] = "def"// array[2] = "ght"