网络

HTTP请求

• GET请求

// URL
NSString *urlStr = @"http://xxxxx.com";
urlStr = [urlStr stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];

NSURL *url = [NSURL URLWithString:urlStr];

// 请求
NSURLRequest *request = [NSURLRequest requestWithURL:url];

• POST请求

// URL
NSString *urlStr = @"http://xxxxx.com";
urlStr = [urlStr stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];

NSURL *url = [NSURL URLWithString:urlStr];

// 请求
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];
request.HTTPMethod = @"POST";
request.HTTPBody = [@"username=123&pwd=123" dataUsingEncoding:NSUTF8StringEncoding];

数据解析

• JSON
  • NSJSONSerialization
• XML
  • SAX: NSXMLParser
  • DOM: GDataXML

NSURLConnection（iOS9已经过期）

• 同步方法
• 异步方法-block
• 异步方法-代理

NSURLSession

• 发送一般的GET\POST请求

NSURLSessionDataTask *task = [[NSURLSession sharedSession] dataTaskWithRequest:request completionHandler:^(NSData *data, NSURLResponse *response, NSError *error) {

}];

[task resume];

• 下载文件 - 不需要离线断点

NSURLSessionDownloadTask *task = [[NSURLSession sharedSession] downloadTaskWithRequest:request completionHandler:^(NSURL *location, NSURLResponse *response, NSError *error) {

}];

[task resume];

• 下载文件 - 需要离线断点
• 开启任务

// 创建session
NSURLSession *session = [NSURLSession sessionWithConfiguration:[NSURLSessionConfiguration defaultSessionConfiguration] delegate:self delegateQueue:[[NSOperationQueue alloc] init]];

// 设置请求头（告诉服务器第1024个字节开始下载）
[request setValue:@"bytes=1024-" forHTTPHeaderField:@"Range"];

// 创建任务
NSURLSessionDataTask *task = [session dataTaskWithRequest:request];

// 开始任务
[task resume];

• 实现代理方法

- (void)URLSession:(NSURLSession *)session dataTask:(NSURLSessionDataTask *)dataTask didReceiveResponse:(NSURLResponse *)response completionHandler:(void (^)(NSURLSessionResponseDisposition))completionHandler
{
    // 打开NSOutputStream

    // 获得文件的总长度

    // 存储文件的总长度

    // 回调
    completionHandler(NSURLSessionResponseAllow);
}

- (void)URLSession:(NSURLSession *)session dataTask:(NSURLSessionDataTask *)dataTask didReceiveData:(NSData *)data
{
    // 利用NSOutputStream写入数据

    // 计算下载进度
}

- (void)URLSession:(NSURLSession *)session task:(NSURLSessionTask *)task didCompleteWithError:(NSError *)error
{
    // 关闭并且清空NSOutputStream

    // 清空任务task
}

• 文件上传
  • 设置请求头
  • 拼接请求体
    • 文件参数
    • 其他参数（非文件参数）
  • NSURLSessionUploadTask

NSURLSessionUploadTask *task = [[NSURLSession sharedSession] uploadTaskWithRequest:request fromData:body completionHandler:^(NSData *data, NSURLResponse *response, NSError *error) {

}];

[task resume];

AFN

• GET

// AFHTTPSessionManager内部包装了NSURLSession
AFHTTPSessionManager *mgr = [AFHTTPSessionManager manager];

NSDictionary *params = @{
                         @"username" : @"111",
                         @"pwd" : @"222"
                         };

[mgr GET:@"http://baidu.com" parameters:params success:^(NSURLSessionDataTask *task, id responseObject) {
    NSLog(@"请求成功---%@", responseObject);
} failure:^(NSURLSessionDataTask *task, NSError *error) {
    NSLog(@"请求失败---%@", error);
}];

• POST

// AFHTTPSessionManager内部包装了NSURLSession
AFHTTPSessionManager *mgr = [AFHTTPSessionManager manager];

NSDictionary *params = @{
                         @"username" : @"111",
                         @"pwd" : @"222"
                         };

[mgr POST:@"http://baidu.com" parameters:params success:^(NSURLSessionDataTask *task, id responseObject) {
    NSLog(@"请求成功---%@", responseObject);
} failure:^(NSURLSessionDataTask *task, NSError *error) {
    NSLog(@"请求失败---%@", error);
}];

• 文件上传

AFHTTPSessionManager *mgr = [AFHTTPSessionManager manager];

[mgr POST:@"http://baidu.com" parameters:@{@"username" : @"111"}
    constructingBodyWithBlock:^(id<AFMultipartFormData> formData) {
        [formData appendPartWithFileURL:[NSURL fileURLWithPath:@"/Users/Mine/Desktop/placeholder.png"] name:@"file" error:nil];
} success:^(NSURLSessionDataTask *task, id responseObject) {
    NSLog(@"-------%@", responseObject);
} failure:^(NSURLSessionDataTask *task, NSError *error) {

}];

UIWebView

• 加载请求

[self.webView loadRequest:[NSURLRequest requestWithURL:[NSURL URLWithString:@"http://www.baidu.com"]]];

• JS和OC的互相调用

//OC调用JS
[webView stringByEvaluatingJavaScriptFromString:@"login();"];

**
 * 通过这个方法完成JS调用OC
 * JS和OC交互的第三方框架：WebViewJavaScriptBridge
 */
- (BOOL)webView:(UIWebView *)webView shouldStartLoadWithRequest:(NSURLRequest *)request navigationType:(UIWebViewNavigationType)navigationType
{
    return YES;
}

• 利用NSInvocation实现performSelector无限参数

#import "NSObject+Extension.h"

@implementation NSObject (Extension)
- (id)performSelector:(SEL)selector withObjects:(NSArray *)objects
{
    // 方法签名(方法的描述)
    NSMethodSignature *signature = [[self class] instanceMethodSignatureForSelector:selector];
    if (signature == nil) {

        [NSException raise:@"错误信息" format:@"%@方法找不到", NSStringFromSelector(selector)];
    }
    
    // NSInvocation : 利用一个NSInvocation对象包装一次方法调用（方法调用者、方法名、方法参数、方法返回值）
    NSInvocation *invocation = [NSInvocation invocationWithMethodSignature:signature];
    invocation.target = self;
    invocation.selector = selector;
    
    // 设置参数
    NSInteger paramsCount = signature.numberOfArguments - 2; // 除self、_cmd以外的参数个数
    paramsCount = MIN(paramsCount, objects.count);
    for (NSInteger i = 0; i < paramsCount; i++) {
        id object = objects[i];
        if ([object isKindOfClass:[NSNull class]]) continue;
        [invocation setArgument:&object atIndex:i + 2];
    }
    
    // 调用方法
    [invocation invoke];
    
    // 获取返回值
    id returnValue = nil;
    if (signature.methodReturnLength) { // 有返回值类型，才去获得返回值
        [invocation getReturnValue:&returnValue];
    }
    
    return returnValue;
}
@end

• 异常捕捉
  • NSException
  • 崩溃统计（第三方）
    • 友盟
    • Flurry
    • Crashlytics