objective-c - nsrange.location 不完全是麻烦 makerange 子串 ios objective c

Question

嗨，我有这个字符串 { "data": [ { "name": "Lorena Trujillo", "id": "500144123"}, { "name": "George Arcila", "id": "520311359"}, { "name": "Laura Victoria Mu\u00f1oz Rincon", "id": "528543677"}, { "name": "Camilo Andres Santacoloma Mejia", "id": "529547832"}],"paging":{“下一个”:“https://graph.facebook.com/537223119/friends?access_token=AAAAAAITEghMBAI7cZBdbAHt3ZC24esi4ZA6O6kFdwU1H0ekDmGQGRZCUZAVW3T6W6fzg50jHsdfsdfsfdsfdsfzdixf1RrTFLzV 96ZBWXAZDZD&limit=5000&offset=5000&__after_id=1000456456455"

y 需要提取 [ 和 ] 之间的子字符串我使用下一个代码

NSRange startRange = [strFriends rangeOfString:@"["];
NSRange endRange = [strFriends rangeOfString:@"]"];
NSString *formData = [strFriends  substringWithRange:NSMakeRange(startRange.location,endRange.location)];
NSLog(@"this is the data %@",formData); 

结果是

[ { "name": "Lorena Trujillo", "id": "500144123"}, { "name": "George Arcila", "id": "520311359"}, { "name": "Laura Victoria Mu\u00f1oz Rincon", "id": "528543677"}, { "name": "Camilo Andres Santacoloma Mejia", "id": "529547832"}],"pagin

知道为什么最后这些字符会出现，"pagin 非常感谢

Answer 1

这是因为 startRange 位置和 endRange 位置都指向字符串内的位置 - 但 subStringWithRange 需要一个位置和一个长度 - 所以你需要计算长度要提取的字符串。像这样:

NSUInteger dataLength = endrange.location - startRange.location;
NSString *formData = [strFriends  substringWithRange:NSMakeRange(startRange.location,dataLength)];

除此之外，您确实需要一个 JSON 解析器来解析 JSON。像这样挑选出小的子串将需要大量工作并且很脆弱。