iphone - 从字符串中获取子字符串

Question

1 US Dollar = 3.673 United Arab Emirates Dirham

如何3.673从此字符串中仅获取值？

我尝试了以下代码，但没有奏效。

NSString *a = [[xmlParser array]objectAtIndex:2];
NSRange startRange = [a rangeOfString:@"="];
NSLog(@"%u",startRange.location+1);
NSRange endRange = [a rangeOfString:@" "];
NSLog(@"%u",endRange.location);
NSString *subString = [a substringWithRange:NSMakeRange(startRange.location + 1, endRange.location)];
NSLog(@"%@",subString);

Answer 1

用这个：

 NSArray *aArray = [a componentsSeparatedByString:@" "]; //your string here
 NSString *dollarValue = [aArray objectAtIndex:4]; //get dollar value from array
 NSLog(@"%@",dollarValue);

Answer 2

我会做类似...

NSArray *words = [string componentsSeparatedByString:@" "];

for (NSString *word in words) {
    //check for equals sign and then take the next one.
}

Answer 3

str = [NSString stringWithFormat:@"1 US Dollar = 3.673 United Arab Emirates Dirham"];  
components = [str componentsSeparatedByCharactersInSet:[NSCharacterSet whitespaceCharacterSet]];
str = [components objectAtIndex:4];
NSLog(@"Str:%@", str);

Answer 4

 NSString *param = nil;
    NSRange start = [a rangeOfString:@"="];
    if (start.location != NSNotFound)
    {
        param = [a substringFromIndex:start.location + start.length];
        NSRange end = [param rangeOfString:@"United"];
        if (end.location != NSNotFound)
        {
            param = [param substringToIndex:end.location];
        }
    }
    NSLog(@"param: %@",param);