手把手教你做iOS的soap应用(webservice)

引自：http://www.cocoachina.com/bbs/read.php?tid=16561

用到的提供soap接口的网址是:http://www.Nanonull.com/TimeService/这个页面有多个方法可以通过soap调用,页面上也有说明.如果用IE的浏览器还能看到此网页提供的wsdl文件.要做soap的webservice首先要了解一些关于webservice和soap的一些基本知识.下面几个网址可能会帮你快速入门.

soap教程:http://www.w3school.com.cn/soap/index.asp
使用WSDL发布WebService:http://blog.csdn.net/meiqingsong/archive/2005/04/04/336057.aspx

为了便于理解,我先讲下soap的大体原理:我们在iphone封装soap请求信息,发送到某个提供soap服务的服务器,如下例中我们用到的http://www.Nanonull.com/TimeService/.服务器能接受和识别soap请求,当它接到请求,就根据客户端的请求情况调用服务器上的某个函数,并将函数返回结果封装成soap反馈信息发送给客户端.客户端接收到soap反馈信息后,进行解析处理,以用户能理解的形式呈现给用户.整个过程就这么简单.

好了,假设现在你已经有关于soap的基础知识(没有也没关系,看了例子,再理解就更好理解了),下面我们开始做soap的例子.

第一步,建一个Hello_SOAP项目.

然后在Hello_SOAPViewController.h中添加如下代码

@interface Hello_SOAPViewController : UIViewController

{

IBOutlet UITextField *nameInput;

IBOutlet UILabel *greeting;

NSMutableData *webData;

NSMutableString *soapResults;

NSXMLParser *xmlParser;

BOOL recordResults;

}

@property(nonatomic, retain) IBOutlet UITextField *nameInput;

@property(nonatomic, retain) IBOutlet UILabel *greeting;

@property(nonatomic, retain) NSMutableData *webData;

@property(nonatomic, retain) NSMutableString *soapResults;

@property(nonatomic, retain) NSXMLParser *xmlParser;

-(IBAction)buttonClick: (id) sender;

- (void)getOffesetUTCTimeSOAP;

然后在Hello_SOAPViewController.xib中将两个输出口和一个动作连接好,这个不用手把手吧?
在Hello_SOAPViewController.m文件中加入以下方法 :

- (void)getOffesetUTCTimeSOAP

{

recordResults = NO;

//封装soap请求消息

NSString *soapMessage = [NSString stringWithFormat:

@"<?xml version=\"1.0\" encoding=\"utf-8\"?>\n"

"<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/\">\n"

"<soap:Body>\n"

"<getOffesetUTCTime xmlns=\"http://www.Nanonull.com/TimeService/\">\n"

"<hoursOffset>%@</hoursOffset>\n"

"</getOffesetUTCTime>\n"

"</soap:Body>\n"

"</soap:Envelope>\n",nameInput.text

];

NSLog(soapMessage);

//请求发送到的路径

NSURL *url = [NSURL URLWithString:@"http://www.nanonull.com/TimeService/TimeService.asmx"];

NSMutableURLRequest *theRequest = [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。

[theRequest addValue: @"text/xml; charset=utf-8" forHTTPHeaderField:@"Content-Type"];

[theRequest addValue: @"http://www.Nanonull.com/TimeService/getOffesetUTCTime" forHTTPHeaderField:@"SOAPAction"];

[theRequest addValue: msgLength forHTTPHeaderField:@"Content-Length"];

[theRequest setHTTPMethod:@"POST"];

[theRequest setHTTPBody: [soapMessage dataUsingEncoding:NSUTF8StringEncoding]];

//请求

NSURLConnection *theConnection = [[NSURLConnection alloc] initWithRequest:theRequest delegate:self];

//如果连接已经建好，则初始化data

if( theConnection )

{

webData = [[NSMutableData data] retain];

}

else

{

NSLog(@"theConnection is NULL");

}

}

这个方法作用就是封装soap请求,并向服务器发送请求.
代码有注释.不重复讲解.soap并不难,难的是没有案例告诉我们怎么把其它平台的soap移植过来,这里我给出了代码,我相信对iphone开发人员的话应该能看懂了.我在下面会把此案例的源代码附上.如果自己做不出来再看我的代码.如果我这样讲您觉得不够细,那说明您的iphone开发还不是太深入,那么您应该用不到soap技术.可以飘过了.
下面的代码是接收信息并解析,显示到用户界面

-(void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response

{

[webData setLength: 0];

NSLog(@"connection: didReceiveResponse:1");

}

-(void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data

{

[webData appendData:data];

NSLog(@"connection: didReceiveData:2");

}

//如果电脑没有连接网络，则出现此信息（不是网络服务器不通）

-(void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error

{

NSLog(@"ERROR with theConenction");

[connection release];

[webData release];

}

-(void)connectionDidFinishLoading:(NSURLConnection *)connection

{

NSLog(@"3 DONE. Received Bytes: %d", [webData length]);

NSString *theXML = [[NSString alloc] initWithBytes: [webData mutableBytes] length:[webData length] encoding:NSUTF8StringEncoding];

NSLog(theXML);

[theXML release];

//重新加載xmlParser

if( xmlParser )

{

[xmlParser release];

}

xmlParser = [[NSXMLParser alloc] initWithData: webData];

[xmlParser setDelegate: self];

[xmlParser setShouldResolveExternalEntities: YES];

[xmlParser parse];

[connection release];

//[webData release];

}

-(void)parser:(NSXMLParser *)parser didStartElement:(NSString *)elementName namespaceURI:(NSString *) namespaceURI qualifiedName:(NSString *)qName

attributes: (NSDictionary *)attributeDict

{

NSLog(@"4 parser didStarElemen: namespaceURI: attributes:");

if( [elementName isEqualToString:@"getOffesetUTCTimeResult"])

{

if(!soapResults)

{

soapResults = [[NSMutableString alloc] init];

}

recordResults = YES;

}

}

-(void)parser:(NSXMLParser *)parser foundCharacters:(NSString *)string

{

NSLog(@"5 parser: foundCharacters:");

if( recordResults )

{

[soapResults appendString: string];

}

}

-(void)parser:(NSXMLParser *)parser didEndElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName

{

NSLog(@"6 parser: didEndElement:");

if( [elementName isEqualToString:@"getOffesetUTCTimeResult"])

{

recordResults = FALSE;

greeting.text = [[[NSString init]stringWithFormat:@"第%@时区的时间是: ",nameInput.text] stringByAppendingString:soapResults];

[soapResults release];

soapResults = nil;

NSLog(@"hoursOffset result");

}

}

- (void)parserDidStartDocument:(NSXMLParser *)parser{

NSLog(@"-------------------start--------------");

}

- (void)parserDidEndDocument:(NSXMLParser *)parser{

NSLog(@"-------------------end--------------");

}

说明下:

-(void)connectionDidFinishLoading:(NSURLConnection *)connection

这个方法是存储接收到的信息

-(void)parser:(NSXMLParser *)parser didEndElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName