【005】iOS网络编程(一)—Http编程

1、在AppDelegate.h中声明方法

-(NSData *) request:(NSString *)urlString;

2、在AppDelegate.m中实现该方法

-(NSData *) request:(NSString *)urlString{
    NSURL *url = [NSURL URLWithString:urlString];
    NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];
    [request setHTTPMethod:@"POST"];
    [request setHTTPBody:[@"Post body" dataUsingEncoding:NSUTF8StringEncoding]];
    NSHTTPURLResponse *response;
    NSError *error;
    NSData * data = [NSURLConnection sendSynchronousRequest:request returningResponse:&response error:&error];
    if(error != nil){
        NSLog(@"Error on load = %@",[error localizedDescription]);
        return nil;
    }
    if([response isKindOfClass:[NSHTTPURLResponse class]]){
        NSHTTPURLResponse *httpResponse = (NSHTTPURLResponse*)response;
        if(httpResponse.statusCode != 200){
            return nil;
        }
        NSLog(@"Headers:%@",[httpResponse allHeaderFields]);
    }
    NSLog(@"%@",[[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding]);
    return data;
}

3、在AppDelegate.m的application()中调用该方法

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
    [self request:@"http://www.xiongshuangquan.cn/Crab.php"];
    return YES;
}

4、后台Php代码如下：Crab.php

<?php
echo "Hi Crab!"
?>

5、运行程序即可看到控制台打印log如下：

2014-08-22 15:10:59.343 TestDemo[16865:1009451] Headers:{
    Connection = "keep-alive";
    "Content-Encoding" = gzip;
    "Content-Type" = "text/html";
    Date = "Fri, 22 Aug 2014 07:10:58 GMT";
    Server = "nginx/1.4.4";
    "Transfer-Encoding" = Identity;
    Via = "10.67.15.22";
    "X-Powered-By" = "PHP/5.3.27";
}
2014-08-22 15:10:59.344 TestDemo[16865:1009451] Hi Crab!