How to send multiple parameterts to PHP server in HTTP post

Question

I\'m sending base64 string to php server and its working well. Now I want to send another parameter as a string. Can anyone tell me what code need to add in below code.

Answer 1

Given a NSDictionary "params" whose keys and values are strings and where every entry represents one parameter (name/value) you can define a helper category:

@interface NSDictionary (FormURLEncoded)
-(NSData*) dataFormURLEncoded;
@end

dataFormURLEncoded returns a properly encoded character sequence from the given parameters in the dictionary.

The encoding algorithm is specified by w3c: URL-encoded form data / The application/x-www-form-urlencoded encoding algorithm

It can be implemented as follows:

First, a helper function which encodes a parameter name, respectively a parameter value:

static NSString* x_www_form_urlencoded_HTML5(NSString* s)
{
    // http://www.w3.org/html/wg/drafts/html/CR/forms.html#application/x-www-form-urlencoded-encoding-algorithm   , Editor's Draft 24 October 2013
    CFStringRef charactersToLeaveUnescaped = CFSTR(" ");
    CFStringRef legalURLCharactersToBeEscaped = CFSTR("!$&'()+,/:;=?@~");
    
    NSString *result = CFBridgingRelease(CFURLCreateStringByAddingPercentEscapes(
                                             kCFAllocatorDefault,
                                             (__bridge CFStringRef)s,
                                             charactersToLeaveUnescaped,
                                             legalURLCharactersToBeEscaped,
                                             kCFStringEncodingUTF8));
    return [result stringByReplacingOccurrencesOfString:@" " withString:@"+"];
}

Finally, dataFormURLEncoded composes the character sequence of the encoded parameters. A "parameter" will be composed by concatenating the encoded name, = and encoded value:

parameter := name "=" value

Then, the parameter list will be composed by concatenating the parameters by separating them by a "&":

parameters  := parameter ["&" parameter]

It can be implemented as below:

@implementation NSDictionary (FormURLEncoded)

-(NSData*) dataFormURLEncoded {
    NSMutableData* data = [[NSMutableData alloc] init];
    BOOL first = YES;
    for (NSString* name in self) {
        @autoreleasepool {
            if (!first) {
                [data appendBytes:"&" length:1];
            }
            NSString* value = self[name];
            NSData* encodedName = [x_www_form_urlencoded_HTML5(name) dataUsingEncoding:NSUTF8StringEncoding];
            NSData* encodedValue = [x_www_form_urlencoded_HTML5(value) dataUsingEncoding:NSUTF8StringEncoding];
            
            [data appendData:encodedName];
            [data appendBytes:"=" length:1];
            [data appendData:encodedValue];
            first = NO;
        }
    }
    return [data copy];
}

@end

Note: The character sequence encodes the strings using Unicode UTF-8.

Example:

Given your parameters:

NSDictionary* params = @{@"a": @"a a", @"b": @"b+b", @"c": @"ü ö"};
NSData* encodedParamData = [params dataFormURLEncoded];

Now, encodedParamData will be added to your body whose content type is application/x-www-form-urlencoded.

The encoded parameter string becomes:

a=a+a&b=b%2Bb&c=%C3%BC+%C3%B6