如何将数据保存在 JSON 字典中并发送 Web 服务后调用？答案

【问题标题】：How to save the data in JSON dictionary and to send the web service post call?如何将数据保存在 JSON 字典中并发送 Web 服务后调用？
【发布时间】：2016-12-19 05:10:57
【问题描述】：

我有两个名为密码字段的文本字段，我将该文本保存在一个名为“Firststring”的字符串中。

我的疑问是如何将字符串值分配给我的 jsonDict 并进行 Web 服务发布调用？

【问题讨论】：

标签： ios objective-c

【解决方案1】：

你的方法是对的，你可以使用 Keys 直接将你的字符串添加到 Dict

NSMutableDictionary *jsonDict = [[NSMutableDictionary alloc] init];
[jsonDict setObject:@"staticname" forKey:@"albert"];
[jsonDict setObject:Firststring forKey:@"password"];

update-1

NSMutableURLRequest *req = [[NSMutableURLRequest alloc] initWithURL:[NSURL URLWithString:@"YOUR URL HERE"]];
[req setHTTPMethod:@"POST"];
 NSError *error = nil;

   NSMutableDictionary *jsonDict = [[NSMutableDictionary alloc] init];
[jsonDict setObject:@"staticname" forKey:@"albert"];
[jsonDict setObject:Firststring forKey:@"password"];

 NSData *data = [NSJSONSerialization dataWithJSONObject:jsonDict 
options:kNilOptions error:&error];
 NSString *postLength = [NSString stringWithFormat:@"%d",[data length]];
[req addValue:postLength forHTTPHeaderField:@"Content-Length"];
[req setHTTPBody:postData];
NSURLSession *session = [NSURLSession sharedSession];

NSURLSessionDataTask *task = [session dataTaskWithRequest:req
                                        completionHandler:^(NSData *data, NSURLResponse *response, NSError *error) {
                                            // Do something 
           NSDictionary *json = [NSJSONSerialization JSONObjectWithData:data options:0 error:nil];
    NSLog(@"%@", json);  
                                        }];

[task resume];

选择 2

// 1
NSURL *url = [NSURL URLWithString:@"YOUR_WEBSERVICE_URL"];
NSURLSessionConfiguration *config = [NSURLSessionConfiguration defaultSessionConfiguration];
NSURLSession *session = [NSURLSession sessionWithConfiguration:config];

// 2
NSMutableURLRequest *request = [[NSMutableURLRequest alloc]  initWithURL:url];
request.HTTPMethod = @"POST";

 // 3
   NSMutableDictionary *jsonDict = [[NSMutableDictionary alloc] init];
[jsonDict setObject:@"staticname" forKey:@"albert"];
[jsonDict setObject:Firststring forKey:@"password"];

 NSError *error = nil;
NSData *data = [NSJSONSerialization dataWithJSONObject:jsonDict 
options:kNilOptions error:&error];


if (!error) {
 // 4
 NSURLSessionUploadTask *uploadTask = [session  uploadTaskWithRequest:request
fromData:data completionHandler:^(NSData *data,NSURLResponse  *response,NSError *error) {
// Handle response here
  // handle response
             NSDictionary *json = [NSJSONSerialization JSONObjectWithData:data options:0 error:nil];
    NSLog(@"%@", json);
}];

// 5
[uploadTask resume];

注意 - 如果你想在 iOS 9 中访问服务器，你需要在你的 .PList 中添加 NSAllowsArbitraryLoads 例如参见 This

【讨论】：

所以之后我不知道如何将数据传递到我的数据库。例如我的 url 是：`http://some xample/api`我需要将这些 json 数据传递到我的服务器然后怎么做。我在问网络服务调用。怎么做
好的，那么我将在哪里将参数传递给 url。你能添加你的两个代码并更新，以便我可以学习如何编码以及在哪里传递 jsonDict
@mack - 例如见这里raywenderlich.com/67081/cookbook-using-nsurlsession
所以你的两个选择是以json格式将参数发送到api对吗？？
真的帮了大忙。我会处理json调用并回来..感谢您的宝贵时间

【解决方案2】：

像这样：

NSDictionary *jsonDict = @{@"staticname":@"albert",
                           @"password":password};

【讨论】：

【解决方案3】：

使用以下方法发布数据。

-(IBAction)login:(id)sender{
        NSMutableDictionary *dict = [[NSMutableDictionary alloc] init];
        [dict setObject:self.txtUsername.text forKey:@"txt_user_email"];
        [dict setObject:self.txtPassword.text forKey:@"txt_user_pass"];
        [self postMethodWithDict:dict andURL:@"http:your API url here" ];

}



-(void) postMethodWithDict:(NSDictionary *)dict andURL:(NSString *)url{

    NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:[NSURL URLWithString:url]];
    [request setHTTPMethod:@"POST"];
    [request setTimeoutInterval:30];

    NSString *boundary = [NSString stringWithFormat:@"14737809831466499882746641449"];
    NSString *contentType = [NSString stringWithFormat:@"multipart/form-data; boundary=%@", boundary];
    [request setValue:contentType forHTTPHeaderField:@"Content-Type"];
    NSMutableData *body = [NSMutableData data];
    [body appendData:[[NSString stringWithFormat:@"--%@\\r\\n", boundary] dataUsingEncoding:NSUTF8StringEncoding]];

NSLog(@"sending data  %@", dict);

    // additional method to call in between
    NSData *data = [self createFormData:dict withBoundary:boundary];
    [body appendData:[[NSString stringWithFormat:@"\\r\\n--%@\\r\\n", boundary] dataUsingEncoding:NSUTF8StringEncoding]];
    [body  appendData:data];
    [request setHTTPBody:body];

    NSURLConnection *conn = [[NSURLConnection alloc]initWithRequest:request delegate:self startImmediately:YES];
    if(conn) {
        // connection success
        NSLog(@"connection success");
    }
    else {
        // deal with error
        NSLog(@"error occured");
    }
}


//  linked method
- (NSData*)createFormData:(NSDictionary*)myDictionary withBoundary:(NSString*)myBounds {
    NSMutableData *myReturn = [[NSMutableData alloc] init];
    NSArray *formKeys = [myDictionary allKeys];
    for (int i = 0; i < [formKeys count]; i++) {
        [myReturn appendData:[[NSString stringWithFormat:@"\r\n--%@\r\n",myBounds] dataUsingEncoding:NSASCIIStringEncoding]];
        [myReturn appendData:[[NSString stringWithFormat:@"Content-Disposition: form-data; name=\"%@\"\r\n\r\n%@",[formKeys objectAtIndex:i],    [myDictionary valueForKey:[formKeys objectAtIndex:i]]] dataUsingEncoding:NSASCIIStringEncoding]];
    }
    return myReturn;
}

使用 NSURLConnection 委托方法来获取你的 api 的所有响应

【讨论】：