我需要等待從SOAP Web服務的響應,我通過調用NSURLConnection的,因爲我需要處理返回的數據,然後從我的課它返回到調用的類..NSURLConnection - 是否可以等待/阻止請求?
這裏是我的代碼:
#import <Foundation/Foundation.h>
@interface UsersBLL : NSObject {
NSMutableData *webData;
NSMutableString *soapResults;
NSXMLParser *xmlParser;
BOOL *recordResults;
NSNumber *EmailCount;
}
@property(nonatomic, retain) NSMutableData *webData;
@property(nonatomic, retain) NSMutableString *soapResults;
@property(nonatomic, retain) NSXMLParser *xmlParser;
-(int)checkEmailAddress:(NSString*)emailAddress;
@end
#import "UsersBLL.h"
@implementation UsersBLL
@synthesize webData;
@synthesize soapResults;
@synthesize xmlParser;
-(id)init {
self = [super init];
return self;
}
-(int)checkEmailAddress:(NSString*)emailAddress {
// Build the SOAP envelope
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"
"<CheckEmailAddress xmlns=\"http://tempuri.org/\">\n"
"<EmailAddress>%@</EmailAddress>\n"
"</CheckEmailAddress>\n"
"</soap:Body>\n"
"</soap:Envelope>\n", emailAddress];
NSLog(soapMessage);
NSURL *url = [NSURL URLWithString:@"http://photoswapper.mick-walker.co.uk/UsersService.asmx?op=CheckEmailAddress"];
NSMutableURLRequest *theRequest = [NSMutableURLRequest requestWithURL:url];
NSString *msgLength = [NSString stringWithFormat:@"%d", [soapMessage length]];
[theRequest addValue: @"text/xml; charset=utf-8" forHTTPHeaderField:@"Content-Type"];
[theRequest addValue: @"http://tempuri.org/CheckEmailAddress" forHTTPHeaderField:@"SOAPAction"];
[theRequest addValue: msgLength forHTTPHeaderField:@"Content-Length"];
[theRequest setHTTPMethod:@"POST"];
[theRequest setHTTPBody: [soapMessage dataUsingEncoding:NSUTF8StringEncoding]];
NSURLConnection *theConnection = [[NSURLConnection alloc] initWithRequest:theRequest delegate:self];
if(theConnection)
{
webData = [[NSMutableData data] retain];
}
else
{
NSLog(@"theConnection is NULL");
}
NSLog(@"%@", EmailCount);
}
-(void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response
{
[webData setLength: 0];
}
-(void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data
{
[webData appendData:data];
}
-(void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error
{
NSLog(@"ERROR with theConenction");
[connection release];
[webData release];
}
-(void)connectionDidFinishLoading:(NSURLConnection *)connection
{
NSLog(@"DONE. Received Bytes: %d", [webData length]);
NSString *theXML = [[NSString alloc] initWithBytes: [webData mutableBytes] length:[webData length] encoding:NSUTF8StringEncoding];
NSLog(theXML);
[theXML release];
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
{
if([elementName isEqualToString:@"CheckEmailAddressResult"])
{
if(!soapResults)
{
soapResults = [[NSMutableString alloc] init];
}
recordResults = TRUE;
}
}
-(void)parser:(NSXMLParser *)parser foundCharacters:(NSString *)string
{
if(recordResults)
{
[soapResults appendString: string];
}
}
-(void)parser:(NSXMLParser *)parser didEndElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName
{
if([elementName isEqualToString:@"CheckEmailAddressResult"])
{
recordResults = FALSE;
NSNumberFormatter *formatter = [[NSNumberFormatter alloc]init];
EmailCount = [formatter numberFromString:soapResults];
[formatter release];
[soapResults release];
soapResults = nil;
}
}
@end
CheckEmailAddress被聲明爲返回一個整數值(我知道它在上面的示例中沒有返回任何內容)。
我想要的是通過CheckEmailAddress方法,返回從Web服務檢索到的值。然而,由於調用NSURLConnection並沒有等到請求完成,我不能這樣做。
如果有人能給我任何潛在的變通方法,我將不勝感激。
正是我正要建議 - 要注意的是,如果它永遠不會返回出於某種原因,你的程序將掛。 – wadesworld 2009-12-13 21:58:20
是的,當我提到一個似乎存在但不響應或由於某種原因無法訪問的主機時,經常會遇到這種情況。但是,將超時設置爲合理的值大部分時間都是這樣。 – Alfonso 2009-12-13 22:19:55
我很抱歉跟進另一個問題,但我看不到如何sendSynchronousRequest可以幫助我獲取數據,解析它並從我的方法返回結果 關注 – 2009-12-13 22:27:04