一：NSURLConnection（IOS9.0已經棄用）是早期apple提供的http訪問方式。以下列出了常用的幾個場景：GET請求，POST請求，Response中帶有json數據 對於NSURLConnection有以下註意事項：（1）sendAsynchronourequest: queue
一：NSURLConnection（IOS9.0已經棄用）是早期apple提供的http訪問方式。以下列出了常用的幾個場景：GET請求，POST請求，Response中帶有json數據
對於NSURLConnection有以下註意事項：（1）sendAsynchronourequest: queue: completionHandler:函數中的queue參數表示的是“handler 這個block運行在queue中，如果queue為mainThread，那麼hanlder就運行在主線程；所以在處理UI的時候需要註意這個參數”
（1）Get請求（返迴文本）
//Request NSMutableURLRequest *urlRequest = [NSMutableURLRequest new]; [urlRequest setURL:[NSURL URLWithString:@"http://XXX.sinaapp.com/test/test.php?namr&id=43"]]; [urlRequest setTimeoutInterval:10.0f]; [urlRequest setHTTPMethod:@"GET"]; [urlRequest setCachePolicy:NSURLRequestReloadIgnoringLocalAndRemoteCacheData]; NSOperationQueue *queue = [[NSOperationQueue alloc]init]; [NSURLConnection sendAsynchronousRequest:urlRequest queue:queue completionHandler:^(NSURLResponse * _Nullable response, NSData * _Nullable data, NSError * _Nullable connectionError) {
//根據回覆Headers，確認是是否為NSHTTPURLResponse的對象 if([response isKindOfClass:[NSHTTPURLResponse class]]){ NSHTTPURLResponse *resHttp = (NSHTTPURLResponse *)response; NSLog(@"status = %ld",resHttp.statusCode);//200 304 401...... NSDictionary *dicHeader = resHttp.allHeaderFields; NSLog(@"headers = %@",dicHeader); } else{ NSLog(@"not http"); }
if(data){ NSString *html = [[NSString alloc]initWithData:data encoding:NSUTF8StringEncoding]; NSLog(@"%@",html); } }];
（2）POST請求（返迴文本）
//Request NSMutableURLRequest *urlRequest = [NSMutableURLRequest new]; [urlRequest setURL:[NSURL URLWithString:@"http://XXX.sinaapp.com/test/test.php"]]; [urlRequest setTimeoutInterval:10.0f]; [urlRequest setHTTPMethod:@"POST"]; [urlRequest setCachePolicy:NSURLRequestReloadIgnoringLocalAndRemoteCacheData]; NSString *strBody = @"p1=abc&p2=12"; [urlRequest setHTTPBody:[strBody dataUsingEncoding:NSUTF8StringEncoding]]; NSOperationQueue *queue = [[NSOperationQueue alloc]init];
[NSURLConnection sendAsynchronousRequest:urlRequest queue:queue completionHandler:^(NSURLResponse * _Nullable response, NSData * _Nullable data, NSError * _Nullable connectionError) { //確認是http if([response isKindOfClass:[NSHTTPURLResponse class]]){ NSHTTPURLResponse *resHttp = (NSHTTPURLResponse *)response; NSLog(@"status = %ld",resHttp.statusCode);//200 304 401...... NSDictionary *dicHeader = resHttp.allHeaderFields; NSLog(@"headers = %@",dicHeader); } else{ NSLog(@"not http"); } if(data){ NSString *html = [[NSString alloc]initWithData:data encoding:NSUTF8StringEncoding]; NSLog(@"%@",html); } }];
（3）Response中有Json數據
//Request
NSMutableURLRequest *urlRequest = [NSMutableURLRequest new];
[urlRequest setURL:[NSURL URLWithString:@"http://XXX.sinaapp.com/test/test.php"]];
[urlRequest setTimeoutInterval:10.0f];
[urlRequest setHTTPMethod:@"POST"];
[urlRequest setCachePolicy:NSURLRequestReloadIgnoringLocalAndRemoteCacheData];
NSString *strBody = @"p1=abc&p2=12";
[urlRequest setHTTPBody:[strBody dataUsingEncoding:NSUTF8StringEncoding]];
NSOperationQueue *queue = [[NSOperationQueue alloc]init];
[NSURLConnection
sendAsynchronousRequest:urlRequest
queue:queue
completionHandler:^(NSURLResponse * _Nullable response, NSData * _Nullable data, NSError * _Nullable connectionError) {
NSError *err2 = nil;
id jsonObject = [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingAllowFragments error:&err2];
if([jsonObject isKindOfClass:[NSDictionary class]]){
NSLog(@"NSDictionary");
NSDictionary *dic = jsonObject;
NSLog(@"dic = %@",dic);
}
else if([jsonObject isKindOfClass:[NSArray class]]){
NSLog(@"NSDictionary");
NSDictionary *arr = jsonObject;
NSLog(@"arr = %@",arr);
}
}];
（4）Request中帶有Json格式數據
//Request
NSMutableURLRequest *urlRequest = [NSMutableURLRequest new];
[urlRequest setURL:[NSURL URLWithString:@"http://XXXX.sinaapp.com/test/test.php"]];
[urlRequest setTimeoutInterval:10.0f];
[urlRequest setHTTPMethod:@"POST"];
[urlRequest setCachePolicy:NSURLRequestReloadIgnoringLocalAndRemoteCacheData];
[urlRequest setValue:@"application/json" forHTTPHeaderField:@"Content-Type"];//這句沒有也沒關係
NSDictionary *dicRequest = @{@"name":@"leo",
@"id":@"456"};
NSData *jsonData = [NSJSONSerialization dataWithJSONObject:dicRequest options:NSJSONWritingPrettyPrinted error:nil];
[urlRequest setHTTPBody:jsonData];
NSOperationQueue *queue = [[NSOperationQueue alloc]init];
[NSURLConnection
sendAsynchronousRequest:urlRequest
queue:queue
completionHandler:^(NSURLResponse * _Nullable response, NSData * _Nullable data, NSError * _Nullable connectionError) {
NSError *err2 = nil;
id jsonObject = [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingAllowFragments error:&err2];
if([jsonObject isKindOfClass:[NSDictionary class]]){
NSLog(@"NSDictionary");
NSDictionary *dic = jsonObject;
NSLog(@"dic = %@",dic);
}
else if([jsonObject isKindOfClass:[NSArray class]]){
NSLog(@"NSDictionary");
NSDictionary *arr = jsonObject;
NSLog(@"arr = %@",arr);
}
}];
伺服器端的處理與返回（將request的值末尾加上_appending，然後返回）
<?php
header('Access-Control-Allow-Origin:*');
$json_string = $GLOBALS['HTTP_RAW_POST_DATA'];
$obj = json_decode($json_string);
//echo $obj->name;
//echo $obj->id;
$arr = array(
"name"=>$obj->name."_appending",
"id"=>$obj->id."_appending");
echo json_encode($arr);
(5)從伺服器下載圖片（啟示就是普通的GET請求，只是將response中的data轉為Image而已）
//Request
NSMutableURLRequest *urlRequest = [NSMutableURLRequest new];
[urlRequest setURL:[NSURL URLWithString:@"https://res.wx.qq.com/mpres/htmledition/images/pic/case-detail/nfhk_l23b6fe.jpg"]];
[urlRequest setTimeoutInterval:10.0f];
[urlRequest setHTTPMethod:@"GET"];
[urlRequest setCachePolicy:NSURLRequestReloadIgnoringLocalAndRemoteCacheData];
[NSURLConnection
sendAsynchronousRequest:urlRequest
queue:[NSOperationQueue mainQueue]
completionHandler:^(NSURLResponse * _Nullable response, NSData * _Nullable data, NSError * _Nullable connectionError) {
UIImage *img = [UIImage imageWithData:data];
[self.imgView setImage:img];
}];
（6）以上所有動作都可以使用代理來做，原理上都是一樣的
NSURLConnectionDataDelegate,
NSURLConnectionDelegate,
NSURLConnectionDownloadDelegate
