无法从Json读取特定数据？
[英]Can't read particular data from Json?
问题描述
I have the json data that has multiple objects in it, i have saved those objects in array but app crushes on next line when i read particular data in a single object. 
我有json数据，其中有多个对象，我已经将这些对象保存在数组中，但是当我读取单个对象中的特定数据时，应用程序会在下一行中粉碎。 here is my code: 这是我的代码：
NSString *myRequestString = [NSString stringWithFormat:@"getSavedSearches=yes&userId=40"];
// Create Data from request
NSData *myRequestData = [NSData dataWithBytes: [myRequestString UTF8String] length: [myRequestString length]];
NSMutableURLRequest *request = [[NSMutableURLRequest alloc] initWithURL: [NSURL URLWithString: url]];
// set Request Type
[request setHTTPMethod: @"POST"];
// Set content-type
[request setValue:@"application/x-www-form-urlencoded" forHTTPHeaderField:@"content-type"];
// Set Request Body
[request setHTTPBody: myRequestData];
// Now send a request and get Response
NSData *returnData = [NSURLConnection sendSynchronousRequest: request returningResponse: nil error: nil];
// Log Response
NSString *response = [[NSString alloc] initWithBytes:[returnData bytes] length:[returnData length] encoding:NSUTF8StringEncoding];
NSLog(@"%@",response);
NSArray *a = [NSJSONSerialization JSONObjectWithData:returnData options:NSJSONReadingMutableLeaves error:nil];
NSLog(@"Sunday: %@",[a description]);
NSDictionary *b = [a objectAtIndex:0];
NSLog(@"%@", [b valueForKey:@"SAVED_NAME"]);
here is the response 这是回应
{"0": {
"EVENT_ID": "19",
"NAME": "asdasd",
"ADDRESS1": "asdasd",
"ADDRESS2": "asdasd",
"START_DATE": "2015-06-04",
"END_DATE": "2015-06-12",
"START_TIME": "2 PM",
"END_TIME": "10 PM",
"SAVED": "1",
"SAVED_NAME": "hello",
"UPDATED_BY": "New Event",
"UPDATED_AT": "2015-06-25 14:13:43"
}, "1": {
"EVENT_ID": "20",
"NAME": "asdasdasdasdasdasdasd",
"ADDRESS1": "asdasd",
"ADDRESS2": "",
"START_DATE": "2015-05-13",
"END_DATE": "2015-05-14",
"START_TIME": "3 PM",
"END_TIME": "4 PM",
"SAVED": "1",
"SAVED_NAME": "yellow",
"UPDATED_BY": "New Event",
"UPDATED_AT": "2015-05-25 14:14:04"
}, "2": {
"EVENT_ID": "22",
"NAME": "Osama",
"ADDRESS1": "add",
"ADDRESS2": "",
"START_DATE": "2015-05-07",
"END_DATE": "2015-05-27",
"START_TIME": "1 AM",
"END_TIME": "3 PM",
"SAVED": "1",
"SAVED_NAME": "yo yo",
"UPDATED_BY": "New Event",
"UPDATED_AT": "2015-05-26 11:38:14"
}, "3": {
"EVENT_ID": "23",
"NAME": "zxczxc",
"ADDRESS1": "zxczxc",
"ADDRESS2": "zxczxc",
"START_DATE": "2015-05-12",
"END_DATE": "2015-05-26",
"START_TIME": "10 AM",
"END_TIME": "2 PM",
"SAVED": "1",
"SAVED_NAME": "hahaha",
"UPDATED_BY": "New Event",
"UPDATED_AT": "2015-05-26 11:55:24"
}, "4": {
"EVENT_ID": "24",
"NAME": "wqeqweqe",
"ADDRESS1": "qweqwe",
"ADDRESS2": "qweqwe",
"START_DATE": "2015-05-05",
"END_DATE": "2015-05-07",
"START_TIME": "2 AM",
"END_TIME": "9 AM",
"SAVED": "1",
"SAVED_NAME": "jajajaja",
"UPDATED_BY": "New Event",
"UPDATED_AT": "2015-05-26 12:53:21"
}, "5": {
"EVENT_ID": "25",
"NAME": "uiooiuuio",
"ADDRESS1": "uiouio",
"ADDRESS2": "uiouio",
"START_DATE": "2015-05-05",
"END_DATE": "2015-05-13",
"START_TIME": "7 AM",
"END_TIME": "3 PM",
"SAVED": "1",
"SAVED_NAME": "asdasdasdasdasdasd",
"UPDATED_BY": "New Event",
"UPDATED_AT": "2015-05-26 12:58:28"
}, "6": {
"EVENT_ID": "26",
"NAME": "asdasdasd",
"ADDRESS1": "asdasdasdas",
"ADDRESS2": "",
"START_DATE": "2015-05-14",
"END_DATE": "2015-05-13",
"START_TIME": "9 AM",
"END_TIME": "10 PM",
"SAVED": "1",
"SAVED_NAME": "xcvxcvxcv",
"UPDATED_BY": "New Event",
"UPDATED_AT": "2015-05-26 16:48:43"
}, "7": {
"EVENT_ID": "37",
"NAME": "Osama",
"ADDRESS1": "asdasd",
"ADDRESS2": "asdasd",
"START_DATE": "2015-05-04",
"END_DATE": "2015-05-12",
"START_TIME": "2 PM",
"END_TIME": "10 PM",
"SAVED": "1",
"SAVED_NAME": "Osama",
"UPDATED_BY": "New Event",
"UPDATED_AT": "2015-06-02 17:07:44"
}, "8": {
"EVENT_ID": "39",
"NAME": "asdas",
"ADDRESS1": "asdasd",
"ADDRESS2": "asdasd",
"START_DATE": "2015-06-03",
"END_DATE": "2015-06-12",
"START_TIME": "7 AM",
"END_TIME": "3 PM",
"SAVED": "1",
"SAVED_NAME": "asdasd",
"UPDATED_BY": "New Event",
"UPDATED_AT": "2015-06-05 18:23:19"
}, "9": {
"EVENT_ID": "40",
"NAME": "asdasd",
"ADDRESS1": "asdasd",
"ADDRESS2": "asdasd",
"START_DATE": "2015-06-03",
"END_DATE": "2015-06-17",
"START_TIME": "8 AM",
"END_TIME": "3 PM",
"SAVED": "1",
"SAVED_NAME": "asdasdasdasd",
"UPDATED_BY": "New Event",
"UPDATED_AT": "2015-06-05 18:26:06"
}, "10": {
"EVENT_ID": "41",
"NAME": "asdasd",
"ADDRESS1": "asdad",
"ADDRESS2": "as",
"START_DATE": "2015-06-09",
"END_DATE": "2015-06-24",
"START_TIME": "2 PM",
"END_TIME": "11 PM",
"SAVED": "1",
"SAVED_NAME": "qeqweqweqweqweqweqweqwewqeqweqweqwqwee",
"UPDATED_BY": "New Event",
"UPDATED_AT": "2015-06-05 18:28:14"
}, "11": {
"EVENT_ID": "42",
"NAME": "asdasd",
"ADDRESS1": "asdasd",
"ADDRESS2": "qweqwe",
"START_DATE": "2015-06-03",
"END_DATE": "2015-06-03",
"START_TIME": "9 AM",
"END_TIME": "9 PM",
"SAVED": "1",
"SAVED_NAME": "iopiop",
"UPDATED_BY": "New Event",
"UPDATED_AT": "2015-06-05 18:29:22"
}, "12": {
"EVENT_ID": "43",
"NAME": "asdasd",
"ADDRESS1": "as",
"ADDRESS2": "adad",
"START_DATE": "2015-06-10",
"END_DATE": "2015-06-18",
"START_TIME": "8 AM",
"END_TIME": "8 PM",
"SAVED": "1",
"SAVED_NAME": "bvnvnvnvbnvbnvbn",
"UPDATED_BY": "New Event",
"UPDATED_AT": "2015-06-05 18:37:36"
}, "13": {
"EVENT_ID": "44",
"NAME": "asdad",
"ADDRESS1": "asdasd",
"ADDRESS2": "qweqwe",
"START_DATE": "2015-06-03",
"END_DATE": "2015-06-17",
"START_TIME": "9 AM",
"END_TIME": "4 PM",
"SAVED": "1",
"SAVED_NAME": "asdasdasd",
"UPDATED_BY": "New Event",
"UPDATED_AT": "2015-06-05 18:41:27"
}}
but my app crashes on a line : NSDictionary *b = [a objectAtIndex:0]; 但我的应用程序崩溃了一行：NSDictionary * b = [a objectAtIndex：0]; and i need to read "SAVED_NAME" data of every object and save it to an Array. 我需要读取每个对象的“SAVED_NAME”数据并将其保存到数组中。
3 个解决方案
解决方案1
2 2015-06-18 10:57:46
That top-level object is a dictionary; 顶级对象是字典; try: 尝试：
NSDictionary *a = [NSJSONSerialization JSONObjectWithData:returnData
options:NSJSONReadingMutableLeaves
error:nil];
NSLog(@"Sunday: %@",[a description]);
NSDictionary *b = a[@"0"];
It doesn't need to be a dictionary as you are using stringified-numbers for the keys; 它不需要是字典，因为您使用字符串数字作为键; but as it stands it is a dictionary. 但现在它是一本字典。
解决方案2
1 已采纳 2015-06-18 11:03:13
Because data you are getting is not Array it is NSDictionary which has keys-"0","1",..... 因为你得到的数据不是数组，所以NSDictionary有键 - “0”，“1”，.....
So Try- 所以试试 -
NSDictionary *a = [NSJSONSerialization JSONObjectWithData:returnData options:NSJSONReadingMutableLeaves
error:nil];
for(int i=0;i<[a count];i++)
{
NSDictionary *b = [a valueForKey:[NSString stringWithFormat:@"%d",i]];
NSLog(@"%@", [b valueForKey:@"SAVED_NAME"]);
}
解决方案3
0 2015-06-18 11:04:56
JSON response mostly in a dictionary. JSON响应主要在字典中。 so you need to change your root object means change NSArray to NSDictionary. 所以你需要更改你的根对象意味着将NSArray更改为NSDictionary。 It will work fine. 它会工作正常。
声明:本站的技术帖子网页，遵循CC BY-SA 4.0协议，如果您需要转载，请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.
相关问题
Xcode，给定的数据不是有效的 JSON，无法从 API 正确读取 JSON - Xcode, The given data was not valid JSON, Can't read the JSON from API properly
JSON 数据无法读取 - JSON data couldn’t be read
SwiftyJSON：无法从JSON读取数组值 - SwiftyJSON: Can't read array value from JSON
IONIC 3 IOS无法从文件中读取数据 - IONIC 3 IOS can't read data from file
无法读取Firebase数据 - Can't read firebase Data
Swift 从 API 解析 json - 无法读取数据，因为它的格式不正确 - Swift parse json from API - The data couldn’t be read because it isn’t in the correct format
无法在 Swift 中显示从 JSON 到 UITableView 的数据 - Can't show data from JSON to UITableView in Swift
无法从plist读取 - Can't read from plist
无法使用Swift读取Firebase数据 - Can't Read Firebase Data with Swift
无法使用FMDB读取数据 - Can't read data using FMDB
相关标签