Parser error Error Domain=NSXMLParserErrorDomain Code=4 "The operation couldn’t be completed."

I am calling a web service as below:

-(void)verifyEmailAndPasswordWebservices
{    
 NSString  *MD5Password = [ self MD5];
 NSLog(@"text field password %@",txt_Password.text);
 NSLog(@"converted password %@",MD5Password);    

N开发者_运维问答SString *soapMsg =[NSString stringWithFormat:
                    @"<?xml version=\"1.0\" encoding=\"utf-8\"?>"
                    "<SOAP-ENV:Envelope SOAP-ENV:encodingStyle=\"http://schemas.xmlsoap.org/soap/encoding/\"xmlns:SOAP-ENV=\"http://schemas.xmlsoap.org/soap/envelope/\" xmlns:xsd=\"http://www.w3.org/2001/XMLSchema\" xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" xmlns:SOAP-ENC=\"http://schemas.xmlsoap.org/soap/encoding/\" xmlns:tns=\"http://php:8393/includes/webservice\">"
                    "<SOAP-ENV:Body>"
                    "<ns1:LoginUserRequest xmlns:ns1=\"http://schemas.xmlsoap.org/soap/envelope/\">"                        
                    "<email xsi:type=\"xsd:string\">%@</email>"
                    "<pass xsi:type=\"xsd:string\">%@</pass>"                   
                    "</ns1:LoginUserRequest>"
                    "</SOAP-ENV:Body>"
                    "</SOAP-ENV:Envelope>",txt_EmailOrMobile.text,MD5Password];



//---print it to the Debugger Console for verification---
NSLog(@"soapMsg..........%@",soapMsg);

NSURL *url = [NSURL URLWithString:@"http://10.0.0.115:8393/includes/webservice/login1.php"];
req = [NSMutableURLRequest requestWithURL:url];

//---set the headers---

NSString *msgLength = [NSString stringWithFormat:@"%d",[soapMsg length]];
[req addValue:@"application/soap+xml; charset=utf-8" forHTTPHeaderField:@"Content-Type"];
[req addValue:@"http://10.0.0.115/includes/webservice/login1.php/LoginUser" forHTTPHeaderField:@"SoapAction"];
[req addValue:msgLength forHTTPHeaderField:@"Content-Length"];

//---set the HTTP method and body---

[req setHTTPMethod:@"POST"];
[req setHTTPBody: [soapMsg dataUsingEncoding:NSUTF8StringEncoding]];

// [activityIndicator startAnimating];

conn = [[NSURLConnection alloc] initWithRequest:req delegate:self];
if (conn)
{
    webData = [[NSMutableData data] retain];
}   
}

When i get the response it give me following error:

DONE. Received Bytes: 422 shows the XML (null) Parser error Error Domain=NSXMLParserErrorDomain Code=4 "The operation couldn’t be completed. (NSXMLParserErrorDomain error 4.)"

I've searched quite a bit on the internet. But not able to find anything. Any help on this please.

NSXMLParserErrorDomain error 4 means that the XML parser was given an empty document. That suggests to me that the input was either null, or you've managed to change it before it's given to the parser.

I had a better look at your code. The problem isn't that you aren't getting a response. It's just that you're not waiting for it. The request you sent is asynchronous, but you're trying to fill your webData variable straight away (i.e. synchronously).

Another possible reson might be that there is no root tag. example:A xml data like this--->

2011-12-22

<days_remaining>
            0
</days_remaining>

Try this code on your encoding method

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