如何通过PHP中的iPhone应用程序响应POST？

Question

I have Objective C code creating an NSUrlConnection as follows:

//prepar request
    NSString *urlString = [NSString stringWithFormat:@"http://ctruman.info/post.php"];
    NSMutableURLRequest *request = [[[NSMutableURLRequest alloc] init] autorelease];
    [request setURL:[NSURL URLWithString:urlString]];
    [request setHTTPMethod:@"POST"];

    //set headers
    NSString *contentType = [NSString stringWithFormat:@"text/xml"];
    [request addValue:contentType forHTTPHeaderField: @"Content-Type"];

    //create the body
    NSString *formData = [[NSString alloc] initWithFormat:@"%@  %@", username.text, password.text];

    NSData *postData = [[NSString stringWithString:formData] dataUsingEncoding:NSUTF8StringEncoding];

    //post
    [request setHTTPBody:postData];

    //get response
    NSHTTPURLResponse* urlResponse = nil;  
    NSError *error = [[NSError alloc] init];  
    NSData *responseData = [NSURLConnection sendSynchronousRequest:request returningResponse:&urlResponse error:&error];  
    NSString *result = [[NSString alloc] initWithData:responseData encoding:NSUTF8StringEncoding];
    NSLog(@"Response Code: %d", [urlResponse statusCode]);
    if ([urlResponse statusCode] >= 200 && [urlResponse statusCode] < 300) {
        NSLog(@"Response: %@", result);
     }  

Then I have a php script that is supposed to read my POST variables that are being sent:

<?php
print('<pre>');
print_r($_POST);
print('</pre>');
?>

When I execute this, NSLog spits out the following:

Array
    (
    )

Why is it not printing out my post variables? Am I making the POST request incorrectly?

Answer 1

As it looks to me, PHP is trying to read your POST submission as if it were a properly formatted PHP POST payload. Instead, you're setting the content-type to XML content -- which probably confuses the heck out of PHP. It's looking for encoded variables, and finding XML.

You've got 2 options:

1. Read in the XML and parse it yourself using PHP: $xml = file_get_contents('php://input'); an example for reading input is here: http://www.codediesel.com/php/reading-raw-post-data-in-php/ then you can parse it with PHP's xml support: http://us.php.net/xml

2. Recode your objective-C to just send normal POST parameters up to the server. I use the ASIHTTPRequest libraries and it's easy. http://allseeing-i.com/ASIHTTPRequest/