Question

I have developed a webservice in PHP. It uses the MySQL database. In this, I have used JSON. I want to fetch data from this webservice in my iPhone app. I have used a function which has one parameter. How can I use this in the iPhone?

Webservice:

<?php

echo getdata($_REQUEST['lastupdate']);

function getdata($lastupdatedate){

    $json = '{"foo-bar": 12345}';



    $obj = json_decode($json);

    //print $obj->{'foo-bar'}; // 12345



    $con = mysql_connect("localhost","un","pwd");



    if (!$con)



    {



    die('Could not connect: ' . mysql_error());



    }

    //print_r($con);



    mysql_select_db("roster", $con);







    $query = "select * from rates where LastUpdated = '".$lastupdatedate."' order by LastUpdated limit 1";

    $rs = mysql_query($query) or die($query);

    //print_r($rs);

    while($row=mysql_fetch_assoc($rs)){

    $record[] = $row;

    }



    $data = json_encode($record);



    header('Cache-Control: no-cache, must-revalidate');

    header('Expires: Mon, 26 Jul 1997 05:00:00 GMT');

    header('Content-type: application/json');

    return $data;

}

?>

I am requesting the URL: http://domain/t1.php?lastupdate=2012-09-01 01:00:00.

Answer 1

You would create an request for http://domain/t1.php?lastupdate=2012-09-01 01:00:00 and then parse your response JSON.

Depending on how your code should function (onload or based on some user action) your code should function similar to this example from raywenderlich.com

Basic code snippets:

- (void)viewDidLoad
{
    [super viewDidLoad];

    dispatch_async(kBgQueue, ^{
        NSData* data = [NSData dataWithContentsOfURL:yourURLValue];
        [self performSelectorOnMainThread:@selector(fetchedData:) 
          withObject:data waitUntilDone:YES];
    });
}

- (void)fetchedData:(NSData *)responseData {
    //parse out the json data
    NSError* error;
    NSDictionary* json = [NSJSONSerialization 
        JSONObjectWithData:responseData //1

        options:kNilOptions 
        error:&error];

    NSArray* JSONResultValues = [json objectForKey:@"yourKey"]; //2

    NSLog(@"Results: %@", JSONResultValues); //3
}