1 NSString * urlString = @"http://www.baidu.com/img/baidu_logo_fqj_10.gif";
 2     //方法一：最直接
 3     NSString * fileName = [urlString lastPathComponent];
 4     NSLog(@"fileName==%@",fileName);
 5     //方法二：根据字符或者字符串分割
 6     NSString * fileName2 = [[NSString alloc] init];
 7     NSArray * separatedArray = [[NSArray alloc] init];
 8     separatedArray = [urlString componentsSeparatedByString:@"/"];
 9     fileName2 = [separatedArray lastObject];
10     NSLog(@"separatedArray==%@",separatedArray);
11     NSLog(@"fileName2==%@",fileName2);
12     //方法三:将链接看成是路劲
13     NSArray * urlCom = [[NSArray alloc] initWithArray:[urlString pathComponents]];
14     NSLog(@"[urlCom lastObject]===%@",[urlCom lastObject]);
15     //方法四：NSRange.它在截取二进制文件的时候十分方便
16     NSString * fileName3;
17     NSRange range = [urlString rangeOfString:@"/" options:NSBackwardsSearch];//NSBackwardsSearch从字符串末尾开始检索
18     if (range.location != NSNotFound) {
19         fileName3 = [urlString substringFromIndex:range.location+1];
20         if ([[fileName3 lowercaseString] hasSuffix:@".gif"]) {//lowercaseString 改变字母为小写 uppercaseString改变字母切大写  capitalizedString 首字母大些转换   ·
21             NSLog(@"fileName3====%@",fileName3);
22         }else{
23         
24         }
25     }else{
26     
27     }