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iOS

Posted by agung laksana
agung laksana
Courses Plus Student 30 Points

I don't really grasp about NSData, NSMutableData, NSString in iOS, what should I learn?

hi,

I actually a beginner in iOS development, I am trying to make method that upload an image to a server. I understand the server side scripting in PHP, but when I am following a tutorial to upload an image in xcode, i don't really grasp about NSData, NSObject, NSMutableData, NSString, it seems the tutorial don't really explain about NSData, NSMutableData, NSString

what kind of topic in iOS development that I should learn to really understand about these things step by step? it seems that I never learn specifically about these things

``` func createBodyWithParameters(parameters: [String: String]?, filePathKey: String?, imageDataKey: NSData, boundary: String) -> NSData { let body = NSMutableData();

    if parameters != nil {
        for (key, value) in parameters! {
            body.appendString("--\(boundary)\r\n")
            body.appendString("Content-Disposition: form-data; name=\"\(key)\"\r\n\r\n")
            body.appendString("\(value)\r\n")
        }
    }

            let filename = "user-profile.jpg"
            let mimetype = "image/jpg"

            body.appendString("--\(boundary)\r\n")
            body.appendString("Content-Disposition: form-data; name=\"\(filePathKey!)\"; filename=\"\(filename)\"\r\n")
            body.appendString("Content-Type: \(mimetype)\r\n\r\n")
            body.appendData(imageDataKey)
            body.appendString("\r\n")



    body.appendString("--\(boundary)--\r\n")

    return body
}



func generateBoundaryString() -> String {
    return "Boundary-\(NSUUID().UUIDString)"
}

} extension NSMutableData {

func appendString(string: String) {
    let data = string.dataUsingEncoding(NSUTF8StringEncoding, allowLossyConversion: true)
    appendData(data!)
}

}