前言
1.網絡請求
系統請求的方法
分為get請求和post請求
1.1、get請求系統提供了兩種方法，一種是Request方式的，一種是URL方式的。下面先說request方式的
NSString * urlStr = @"http://172.16.101.125:8080/wisdombus-controller/mobile/class/queryBusLineList?corpId=0";
NSURL * url = [NSURL URLWithString:urlStr];
NSURLSession * senssion = [NSURLSession sharedSession];//網絡請求管理者
NSMutableURLRequest * request = [NSMutableURLRequest requestWithURL:url];//創建請求對象
//創建網絡數據請求任務的對象
NSURLSessionDataTask * task1 = [senssion dataTaskWithRequest:request completionHandler:^(NSData * _Nullable data, NSURLResponse * _Nullable response, NSError * _Nullable error) {
//由NSData對象獲取json字符串
NSString * string = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
NSLog(@"%@",string);
//NSData數據轉字典
NSDictionary * dic = [NSJSONSerialization JSONObjectWithData:data options:0 error:nil];
NSLog(@"%@",dic);
//回到主線程
[self performSelector:@selector(actionWithString:) onThread:[NSThread mainThread] withObject:string waitUntilDone:YES];
}];
[task1 resume];
get請求url方式
NSString * urlStr = @"http://172.16.101.125:8080/wisdombus-controller/mobile/class/queryBusLineList?corpId=0";
NSURL * url = [NSURL URLWithString:urlStr];
//網絡請求管理者
NSURLSession * senssion = [NSURLSession sharedSession];
//創建網絡數據請求任務的對象
NSURLSessionDataTask * task2 = [senssion dataTaskWithURL:url completionHandler:^(NSData * _Nullable data, NSURLResponse * _Nullable response, NSError * _Nullable error) {
//獲取json字符串
NSString * string = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
NSLog(@"%@",string);
}];
[task2 resume];
1.2、post請求
NSString * urlStr = @"http://172.16.101.125:8080/wisdombus-controller/mobile/class/queryBusLineList";
NSURL * url = [NSURL URLWithString:urlStr];
NSURLSession * senssion = [NSURLSession sharedSession];//網絡請求管理者
NSMutableURLRequest * Postrequest = [NSMutableURLRequest requestWithURL:url];
Postrequest.HTTPMethod = @"POST";
//設置包體
Postrequest.HTTPBody = [@"username=520it&pwd=520it" dataUsingEncoding:NSUTF8StringEncoding];
//創建任務
NSURLSessionDataTask * task = [senssion dataTaskWithRequest:Postrequest completionHandler:^(NSData * _Nullable data, NSURLResponse * _Nullable response, NSError * _Nullable error) {
NSLog(@"%@",[NSJSONSerialization JSONObjectWithData:data options:0 error:nil]);
NSString * string = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
[self performSelector:@selector(actionWithString:) onThread:[NSThread mainThread] withObject:string waitUntilDone:YES];
}];
[task resume];
第三方網絡請求--AFNetWorking
在使用網絡請求的控制器中引入頭文件
#import <AFNetworking/AFNetworking.h>
創建請求管理者，并設置相關屬性
//創建請求管理者
AFHTTPSessionManager * sessionManager = [AFHTTPSessionManager manager];
//上傳設置
sessionManager.requestSerializer = [AFHTTPRequestSerializer serializer];//普通格式上傳
//sessionManager.requestSerializer = [AFJSONRequestSerializer serializer]; // 上傳JSON格式
sessionManager.requestSerializer.timeoutInterval = 10.0f;
//返回數據設置
sessionManager.responseSerializer = [AFHTTPResponseSerializer serializer];//自己動手解析
//sessionManager.responseSerializer = [AFJSONResponseSerializer serializer]; // AFN會JSON解析返回的數據
// 個人建議還是自己解析的比較好，有時接口返回的數據不合格會報3840錯誤，大致是AFN無法解析返回來的數據
sessionManager.responseSerializer.acceptableContentTypes = [NSSet setWithObjects:@"text/plain", @"text/json", @"application/json", @"text/javascript", @"text/html",@"charset=utf-8", nil];
//創建參數和參數值字典
NSDictionary * dic = @{@"corpId":@"0"};
NSString * urlString = @"http://172.16.101.125:8080/wisdombus-controller/mobile/class/queryBusLineList";
post請求
[sessionManager POST:urlString parameters:dic progress:nil success:^(NSURLSessionDataTask * _Nonnull task, id _Nullable responseObject) {
NSLog(@"%@",responseObject);
self.textView2.text = [NSString stringWithFormat:@"%@",responseObject];
} failure:^(NSURLSessionDataTask * _Nullable task, NSError * _Nonnull error) {
NSLog(@"%@",error);
}];
get請求
[sessionManager GET:urlString parameters:dic progress:^(NSProgress * _Nonnull downloadProgress) {
} success:^(NSURLSessionDataTask * _Nonnull task, id _Nullable responseObject) {
NSLog(@"%@",responseObject);
self.textView2.text = [NSString stringWithFormat:@"%@",responseObject];
} failure:^(NSURLSessionDataTask * _Nullable task, NSError * _Nonnull error) {
NSLog(@"%@",error);
}];
注意：系統的網絡請求的block中請求改變外部變量需要做特殊處理，但是第三方的不需要
2.獲取數據，并處理數據
對于數據的處理主要是兩種：
一種是NSData轉json字符串
NSString * string = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
一種是NSData數據轉字典
NSDictionary * dic = [NSJSONSerialization JSONObjectWithData:data options:0 error:nil];
3.獲取導數據后的非空處理
對于獲取到的數據，如果不做非空處理，很容易出現數組越界的情況。所以必須得處理，但是不同的后臺開發人員，寫的接口字段非空時返回的形式多種多樣，所以要綜合處理多種情況，才能避免出錯。
1、對于數組對象，需要判斷元素的個數和數組是否為空
if (self.busLineArr.count == 0||self.busLineArr == nil) {
[self showErrorMessage:@"暫時不能進行切換"];
return;
}
2、對于字符串對象，需要判斷nil、NSNull對象、@“”、@“null”,等4種情況
if (([str isKindOfClass:[NSNull class]]||str == nil||[[NSString stringWithFormat:@"%@",str] length] < 1||[[NSString stringWithFormat:@"%@",str] isEqualToString:@"(null)"])) {//字符串對象為空
}else{//不為空
}
4.圖片的上傳
圖片上傳格式比較固定
NSError *error = nil;
NSURLResponse *response = [NSURLResponse new];
NSString *imageStr = @"http://172.16.101.125:8080/wisdombus-controller/mobile/auth/uploadIMG.do";
NSURL *url = [NSURL URLWithString:imageStr];
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];
// 設置請求方法
[request setHTTPMethod:@"POST"];
// 設置請求體
[request setHTTPBody:_imageData];
// 設置請求頭的內容的類型
[request setValue:[NSString stringWithFormat:@"cesi%.0f.png",[[NSDate date] timeIntervalSince1970]] forHTTPHeaderField:@"fileName"];//圖片文件名字
[request setValue:[NSString stringWithFormat:@"%lu",(unsigned long)_imageData.length] forHTTPHeaderField:@"fileSize"];//大小
[request setValue:[NSString stringWithFormat:@"%@"[[NSUserDefaults standardUserDefaults] objectForKey:@"uuid"]] forHTTPHeaderField:@"userId"];//
[request setValue:[NSString stringWithFormat:@"%d",2] forHTTPHeaderField:@"type"];
NSString *contentType = [NSString stringWithFormat:@"Content-Type multipart/form-data; boundary=%@", kBoundary];
[request setValue:contentType forHTTPHeaderField:@"Content-Type"];
// 發送異步請求
NSData *responseData = [NSURLConnection sendSynchronousRequest:request returningResponse:&response error:&error];
if (!error && responseData) {
NSDictionary *dic = [NSJSONSerialization JSONObjectWithData:responseData options:NSJSONReadingMutableLeaves error:&error];
if ([[dic objectForKey:@"result"] isEqualToString:@"true"]) {
//上傳成功
}else {
//上傳錯誤
}
}else if (error) {
//操作失敗
}
5.圖片的下載問題
圖片加載影響主線程，所以要放到子線程中這里用GCD加載
dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);
dispatch_async(queue, ^{
NSString * urlStr = @"http://img.taopic.com/uploads/allimg/140326/235113-1403260I05466.jpg";
UIImage * userImag = [UIImage imageWithData:[NSData dataWithContentsOfURL:[NSURL URLWithString:urlStr]]];
if (userImag != nil) {//請求成功
dispatch_async(dispatch_get_main_queue(), ^{//返回主線程
self.imageView.image = userImag;
});
}else{//請求失敗，或請求不到圖片
}
});
