UItextFields Data to JSON - objective-c

Question

i have two UItextFields, userNameTextField and passwordTextField and a UIbutton connection. I would like to have what the user typed in the userNametextField and the passwordTextField, How i can do this please ?? thanks for your answer.
#pragma mark - User auhtentification
-(IBAction)userAuthentificate{
BOOL loginValid = YES;
BOOL passwordValid = YES; // Not specified yet
// contrioll d'interfac__ on test login et password
if (loginValid && passwordValid) {
NSString *jsonRequest = #"{\"login\":\"Samir\",\"password\":\"test\",\"mail\":\"test#gmail.com\"}";
// NSString *jsonRequest = #"{\"login\":\"Samir\",\"password\":\"test\",\"mail\":\"samir#gmail.com\",\"editor\":\"1\"}";
NSString *request_url =#"http:.../register"; // Url WS
NSURL *url = [NSURL URLWithString:request_url];
self.currentRequest = [ASIFormDataRequest requestWithURL:url];
currentRequest.delegate =self;
NSData *requestData = [NSData dataWithBytes:[jsonRequest UTF8String] length:[jsonRequest length]];
[self.currentRequest appendPostData:requestData];
[self.currentRequest setRequestMethod:#"POST"];
[self.currentRequest startSynchronous];
}
}

Answer 1

You can put something like this in the place of your jsonRequest string (the code uses the SBJson framework):
NSDictionary *container = [[NSDictionary alloc] initWithObjectsAndKeys:
[loginTextField text], #"login",
[passwordTextField text], #"password",
[mailTextField text], #"mail"];
NSString *jsonString = [container JSONRepresentation];
// don't forget to release container if not using ARC AFTER creating the NSData object

Answer 2

How about a simple string replacement?
NSString *jsonRequest = [NSString stringWithFormat:#"{\"login\":\"%#\",\"password\":\"%#\",\"mail\":\"%#\"}", userNameTextField.text, passwordTextField.text, emailtextField.text];

Answer 3

Use
NSString *jsonRequest = [NSString stringWithFormat:#"{\"login\":\""%#"\",\"password\":\""%#"\",\"mail\":\"test#gmail.com\"}",userNameTextField.text,passwordTextField.text];