String Class and Spark Variable

Firmware
5

@christine @bryce

This particle.variable() always seems to give me problems. Presently I need to figure out how to send a group of variables to a webpage for further processing, seems like packaging the variables as a fake jSON object may be a good solution, but before I get to that, the Particle Firmware Reference has a strange line at

https://docs.particle.io/reference/firmware/photon/#particle-variable-

The line is

  if (Particle.variable("mess", message)==false)
      // variable not registered!
 Particle.variable("mess2", aString);

The syntax here confuses me, could someone please put in some curly brackets as needed or just change the code to something like

  if (Particle.variable("mess", message)==false){
      // variable not registered!
 }
 Particle.variable("mess2", aString);

since the present Firmware example seems to never let “aString” work, unless you somehow make the first “message” char array pointer become not registered! :fearful:

Anyway if I ignore the example code, my working code looks like:

String theString;
int x1,y1,x2,y2,x3,y3;

void setup()
{
   void random_seed_from_cloud(unsigned int seed);

    Particle.variable("myString", theString);
}

void loop()
{
    x1 = random(1, 99);
    y1 = random(1, 99);
    x2 = random(1, 99);
    y2 = random(1, 99);
    x3 = random(1, 99);
    y3 = random(1, 99);

   theString = String( "x1=" + String(x1) + ", y1=" + String(y1) + ", x2=" + String(x2) + ", y2="+String(y2) + ", x3=" + String(x3) + ", y3=" + String(y3) );
   
}

So if I throw something like this into my browser

https://api.particle.io/v1/devices/00000000000/myString?access_token=aaaaaaaaaaaaaaa

where the 000000000 are my ID and the aaaaaaaaaaaa are my access token then I get a result like

{
  "cmd": "VarReturn",
  "name": "myString",
  "result": "x1=17, y1=30, x2=21, y2=23, x3=47, y3=37",
  "coreInfo": {
    "last_app": "",
    "last_heard": "2015-11-05T06:37:15.434Z",
    "connected": true,
    "last_handshake_at": "2015-11-05T06:34:52.260Z",
    "deviceID": "00000000000",
    "product_id": 6
  }
}

Which looks reasonably useful. Now, I just have to remember how to use AJAX to load this back into javascript and I think I am set.

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