iOS请求webservice接口需要明确知道什么信息

公司只给了一个wsdl接口能够请求出数据吗
    NSString *soapMsg = [NSString stringWithFormat:
                         @"<?xml version='1.0' encoding='GB2312' standalone='yes' ?>"
                         @"<soap:Envelope "
                         "xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" "
                         "xmlns:xsd=\"http://www.w3.org/2001/XMLSchema\" "
                         "xmlns:soap=\"http://www.w3.org/2003/05/soap-envelope\">"
                         "<soap:Body>"
                         "<  方法名怎么在wsdl接口里面找到  xmlns=\"命名空间怎么找到">"
                         
                         
                         "</方法名>"
                         "</soap:Body>"
                         "</soap:Envelope>"];
    NSURL *url = [NSURL URLWithString: @"http://x.x.x.x：x/soap/Service?wsdl"];
    // 根据上面的URL创建一个请求
    NSMutableURLRequest *req = [NSMutableURLRequest requestWithURL:url];
    NSString *msgLength = [NSString stringWithFormat:@"%d", [soapMsg length]];
    // 添加请求的详细信息，与请求报文前半部分的各字段对应
    [req addValue:@"application/soap+xml; charset=utf-8" forHTTPHeaderField:@"Content-Type"];    [req addValue:msgLength forHTTPHeaderField:@"Content-Length"];
    // 设置请求行方法为POST，与请求报文第一行对应
    [req setHTTPMethod:@"POST"];
    // 将SOAP消息加到请求中    [req setHTTPBody: [soapMsg dataUsingEncoding:NSUTF8StringEncoding]];
    // 创建连接
    conn = [[NSURLConnection alloc] initWithRequest:req delegate:self];
    if (conn) {
        webData = [NSMutableData data];
    }