ios下通过webservice获取数据

经历了两天的摸索，终于成功获取了数据，因为公司要做一个停车入库的信息查询，所以需要访问webservice的接口，由于没有接触过webservice,所以第一天就是各种搜索资料，类库，各种尝试，甚至是没有用soap封装请求头就直接post请求数据，结果是请求回来的xml是错误，因此，第二天开始静下心来看网上的讲解，把自己的经历及请求过程记录如下：

主要参考如下两个资源（非常非常感谢）

http://www.cocoachina.com/bbs/read.php?tid-98388-page-1.html（自己封装独立类调用ASI方法实现）

http://blog.csdn.net/a6472953/article/details/9813799（最原始的经典实现方式）

我用第一种方法实现，关于参数注释第一篇基本都已说明，需要的参数只有如下：

#define P_SYSTEM_URL @"http://公网地址:端口/" // 不加*.asmx(*是指端口后.asmx前所有部分，这部分为第二个宏定义)
#define G_WS_TODOCENTER @"*.asmx" // (*是指端口后.asmx前所有部分)
#define G_WEBSERVICE_NAMESPACE @"http://tempuri.org/"  // (如果没有指定命名空间，默认为http://tempuri.org/)
#define G_WS_TODOCENTER_GETWORKFLOWTODOCOUNT xxx  // (请求的方法名)
//#define P_USER_NAME  // 可以不设定，代码中相关注释即可
//#define P_PASSWORD   // 可以不设定，代码中相关注释即可

//---------------------------------------对请求的理解------------------------------------------

//1、初始化SOAP消息体
    NSString * soapMsgBody1 = [[NSString alloc] initWithFormat:
                               @"<?xml version="1.0" encoding="utf-8"?> "
                               "<soap:Envelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" "
                               "xmlns:xsd="http://www.w3.org/2001/XMLSchema" "
                               "xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/"> "
                               "<soap:Body> "
                               "<%@ xmlns="%@"> ", wsName, xmlNS];

NSString * soapMsgBody2 = [[NSString alloc] initWithFormat:
                               @"</%@> "
                               "</soap:Body> "
                               "</soap:Envelope>", wsName];

加粗部分为固定，需要改变的是wsName和xmlNS，wsName是webservice名即为上面定义的G_WS_TODOCENTER_GETWORKFLOWTODOCOUNT，xmlNS为命名空间即为上面定义的G_WEBSERVICE_NAMESPACE

//2、生成SOAP调用参数
    NSString * soapParas = [[NSString alloc] init];
    soapParas = @"";
    if (![wsParas isEqual:nil]) {
        int i = 0;
        for (i = 0; i < [wsParas count]; i = i + 2) {
            soapParas = [soapParas stringByAppendingFormat:@"<%@>%@</%@> ",
                         [wsParas objectAtIndex:i],
                         [wsParas objectAtIndex:i+1],
                         [wsParas objectAtIndex:i]];
        }
    }

//3、生成SOAP消息
    NSString * soapMsg = [soapMsgBody1 stringByAppendingFormat:@"%@%@", soapParas, soapMsgBody2];

ASIHTTPRequest * theRequest = [ASIHTTPRequest requestWithURL:url];
    NSString *msgLength = [NSString stringWithFormat:@"%d", [soapMsg length]];
    
    //以下对请求信息添加属性前四句是必有的，第五句是soap信息。
    [theRequest addRequestHeader:@"Content-Type" value:@"text/xml; charset=utf-8"];
    [theRequest addRequestHeader:@"SOAPAction" value:[NSString stringWithFormat:@"%@%@", xmlNS, wsName]];
    
    [theRequest addRequestHeader:@"Content-Length" value:msgLength];
    [theRequest setRequestMethod:@"POST"];
    [theRequest appendPostData:[soapMsg dataUsingEncoding:NSUTF8StringEncoding]];
    
    [theRequest setDefaultResponseEncoding:NSUTF8StringEncoding];
    
    return theRequest;

// -------------自己拼接-----------

    NSString *soapMessage = [NSString stringWithFormat:
                             @"<?xml version="1.0" encoding="utf-8"?> "
                             "<soap:Envelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/"> "
                             "<soap:Body> "
                             "<GetMyRecord xmlns="http://tempuri.org/"> "
                             "<参数名1>参数1值</参数名1> "

　　　　　　　　　　"<参数名2>参数2值</参数名2> "
                             "</GetMyRecord> "
                             "</soap:Body> "
                             "</soap:Envelope> "
                             ];

    
    NSURL *url = [NSURL URLWithString:@"请求连接（.asmx格式）"];
    NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];
    NSString *msgLength = [NSString stringWithFormat:@"%d", [soapMessage length]];
    
    //以下对请求信息添加属性前四句是必有的，第五句是soap信息。
    [request addValue: @"text/xml; charset=utf-8" forHTTPHeaderField:@"Content-Type"];
    [request addValue: @"命名空间/方法名（或叫webservice名称）" forHTTPHeaderField:@"SOAPAction"];
    
    [request addValue: msgLength forHTTPHeaderField:@"Content-Length"];
    [request setHTTPMethod:@"POST"];
    [request setHTTPBody: [soapMessage dataUsingEncoding:NSUTF8StringEncoding]];
    
    //请求
//    NSURLConnection *theConnection = [[NSURLConnection alloc] initWithRequest:theRequest delegate:self];
    [NSURLConnection sendAsynchronousRequest:request queue:[NSOperationQueue mainQueue] completionHandler:^(NSURLResponse *response, NSData *data, NSError *connectionError) {
        [self parserWithData:data];  // 自定义的parserWithData（XML解析方法）
    }];