Pass string with ampersand (&) from iOS to PHP/MySQL with NSURLSession - php

Question

I'm passing a large set of strings to my server from iOS (Swift) to a PHP file via POST. Unfortunately, if a user places an ampersand (&) in a field, the rest of the field is lost. I understand why (& signifies the next field in the message) but I'm not sure how to fix.
func UploadToSql(plan: LessonPlan, isNew: Bool, callBack: ((data: NSData!, response: NSURLResponse!, error: NSError!) -> Void)?) {
let url = NSURL(string: "https://myserver.com/receive.php")!
var request:NSMutableURLRequest = NSMutableURLRequest(URL:url)
var bodyData = "Author=\(plan.author)&title=\(plan.title)&grade=\(plan.grade)&date=\"\(plan.date)\"&element1=\(plan.element1)&objective1=\(convertedFields[0])&element2=\(plan.element2)&objective2=\(convertedFields[1])&element3=\(plan.element3)&objective3=\(convertedFields[2])&coreProcess1=\(plan.coreProcess1)&coreStrand1=\(plan.coreStrand1)&coreStandard1=\(plan.coreStandard1)&coreProcess2=\(plan.coreProcess2)&coreStrand2=\(plan.coreStrand2)&coreStandard2=\(plan.coreStandard2)&coreProcess3=\(plan.coreProcess3)&coreStrand3=\(plan.coreStrand3)&coreStandard3=\(plan.coreStandard3)&media1=\(plan.media1)&media2=\(plan.media2)&media3=\(plan.media3)&media4=\(plan.media4)&media5=\(plan.media5)&media6=\(plan.media6)&repertoire1=\(convertedFields[3])&repertoire2=\(convertedFields[4])&repertoire3=\(convertedFields[5])&process=\(convertedFields[6])&assessment=\(convertedFields[7])&stateCat1=\(plan.stateCat1)&stateCat2=\(plan.stateCat2)&stateCat3=\(plan.stateCat3)&stateStand1=\(plan.stateStand1)&stateStand2=\(plan.stateStand2)&stateStand3=\(plan.stateStand3)&comment=\(plan.comment)&shared=\(sharedInt!)&authorName=\(plan.authorName)" + planID
request.HTTPMethod = "POST"
request.HTTPBody = bodyData.dataUsingEncoding(NSUTF8StringEncoding)
let task = NSURLSession.sharedSession().dataTaskWithRequest(request) {
data, response, error in
if error != nil {
println("error=\(error)")
return
}
println("response = \(response)")
callBack?(data: data, response: response, error: error)
return
}
task.resume()
}

Answer 1

Typically for a webrequest like that it uses % followed by the ascii hex value. The hex value for & is 26, so it would be %26
google.com/#q=red%26white is example of a google search for red&white, which uses that replacement
Its called URL encoding or percent encoding and here is another question with an answer on how to do more broad URL encoding: stackoverflow.com/questions/24551816/swift-encode-url
Note that you would have to URL encode each element you were interpolating into the string, not the whole result string, as you want to keep your &'s that separate parameters.

Answer 2

This one is working for me. I am also using PHP/MySQL with NSURLSession.
func stringByAddingPercentEncodingForFormData(plusForSpace: Bool=false) -> String? {
let unreserved = "*-._"
let allowed = NSMutableCharacterSet.alphanumericCharacterSet()
allowed.addCharactersInString(unreserved)
if plusForSpace {
allowed.addCharactersInString(" ")
}
var encoded = stringByAddingPercentEncodingWithAllowedCharacters(allowed)
if plusForSpace {
encoded = encoded?.stringByReplacingOccurrencesOfString(" ",
withString: "+")
}
return encoded
}
Found above function from this link: http://useyourloaf.com/blog/how-to-percent-encode-a-url-string/.