Search code examples
phpiosjsonstring-parsing

JSON parsing: from PHP5 ( which attacks a database: mySQL ) ios5 iphone

I hope someone can help me put because I've trying the whole day :( ( newly stuff )

I have a database mySQL, which contains one table "products" ( two rows : "id" and "stock" ). And I want my ios5 app to send an "id" and receive the "stock" of that product.

In my PHP code:

echo json_encode(array(
     'id'=>$id,
     'stock'=>$stock, ));

Which I believe sends a JSON to my app, my app receives this JSON in a function called:

- (void)requestFinished:(ASIHTTPRequest *)request
{    
    NSString *responseStringWEB = [request responseString];
    NSLog(@"STRING:: %@ \n", responseStringWEB); //3
    NSDictionary *responseDict = [responseStringWEB JSONValue];
    NSLog(@"DICT: %@ \n", responseDict); //3
    NSString *id_producto = [responseDict objectForKey:@"id"];
    NSString *stock = [responseDict objectForKey:@"stock"];
    NSLog(@"ID: %@\n", id_producto); //3
    NSLog(@"stock: %@", stock); //3
}

and checking the console I get:

**`STRING`::**
Connection establishedDatabase selected..
***{"id":"3","stock":"46"}***
Connection closedDesconectado
2011-12-26 18:58:57.170 CaeDeCajon[1998:16403] Error Domain=NSCocoaErrorDomain Code=3840 "The operation couldn’t be completed. (Cocoa error 3840.)" (JSON text did not start with array or object and option to allow fragments not set.) UserInfo=0x984aeb0 {NSDebugDescription=JSON text did not start with array or object and option to allow fragments not set.}
2011-12-26 18:58:57.171 CaeDeCajon[1998:16403] **`DICT`**: (null)
2011-12-26 18:58:57.171 CaeDeCajon[1998:16403] **`ID`**: (null)
2011-12-26 18:58:57.171 CaeDeCajon[1998:16403] **`stock`**: (null)

The question is : I do not know what format the JSON is coming ( array, How should I parse the NSstring responseStringWEB to get those two values ( ID and STOCK ). It seems I receive them from the database but I do not reach to extract them.

HELP :) thank you ,

EDITING::

Thanks. It really Helped.

It seemed that there has had something to do with the multiple echos I used in the PHP code. Now I only have one echo, sending data in json format. It works perfectly with my database and my app: I receive the whole table ( "id" and "stock" ) of all items. Thanks.

But I have found another obstacle ( no wonder ), is that I need to change the database once the products have been sold, and as they´re not usually sold 1 by 1 must post arrays into PHP,, my intention is to POST the id and reductor(reductor represent how many products of that "id" were sold ) of the products/items affected ( array_id and array_reductor).

IOS5 CODE:

NSArray *array_id=[[NSArray alloc]initWithObjects:@"0",@"3",@"5", nil];

//with the id products;

NSArray *array_reductor=[[NSArray alloc]initWithObjects:@"10",@"5",@"40", nil];

//with the number of products sold ( so I have to decrease the previous stock number in the database by these to obtain the current stock numbers ).

NSURL *url=[[NSURL alloc]initWithString:@"http://www.haveyourapp.com/promos/"];
ASIFormDataRequest *request = [ASIFormDataRequest requestWithURL:url];
[request setPostValue:array_id forKey:@"id"];
[request setPostValue:array_reductor forKey:@"reductor"];

[request setDelegate:self];
[request startAsynchronous];

MY PHP FILE:

if (isset($_POST['id'])&&isset($_POST['reductor'])) // check if data is coming {

$id = array();          // I create arrays
$reductor = array();

$id=$_POST['id'];             // and store arrays in them ( At least is what I believe )
$reductor=$_POST['reductor'];

$connection = new createConnection(); //i created a new object
$connection->connectToDatabase(); // connected to the database
$connection->selectDatabase();

/////////////////////////////////////////////////////////////////////////////////////////////////////////////// Stock reduction in the items affected////////////////////////////////


$num=mysql_numrows($id);
$i=0;
$stock_anterior=array();
while ($i < $num) {

$query=" SELECT  stock FROM productos WHERE id = $id[$i]";
$stock_anterior[$i] = mysql_query($query);
++$i;
}


$l=0;

$num2=mysql_numrows($id);

while ($l < $num2) {

$stock_reductor[$l] = $stock_anterior[$l] - $reductor[$l];

$query = "UPDATE productos SET stock = '$stock_reductor[$l]' WHERE id = $id[$l] ";
mysql_query($query);


++$l;

}



$connection->closeConnection();

But my code is not working, I don not know if the problem is in my app or in the PHP file ( likely ), but how can I receive those two arrays and work with them????

Thanks in advance

I spend a lot of time on stack Overflow: VERY USEFULLLLLLLL!!!!!

Solution

  • Check the PHP script output using a tool such as HTTPScoop. I suspect that something is wrong, based on the console output, which contains the lines Connection establishedDatabase selected.. and Connection closedDesconectado...

    **`STRING`::**
Connection establishedDatabase selected..
***{"id":"3","stock":"46"}***
Connection closedDesconectado

    It looks like you've got some logging from that script that is printed before the JSON starts, which isn't accepted by the JSON parser on the iOS end.