Issue when assigning result to a string about asynchttprequest HOT 2 CLOSED

using .str(); is the answer
String responseResult = request->responseText();
Serial.println(responseResult.c_str());

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Serial.println() should work OK with a String argument. In any event responseText() returns the data available at the time of the call and deletes it from the buffer. In your case you are doing it at readyState 4 so it should be all of the data, but consider if you are getting a long response and taking the data with responseText() in an onData callback at readyState 3. You want each call to pickup where the last left off.

So is it possible that you had something like:

String responseResult = request->responseText();
Serial.println(request->responseText());

In that case responseResult would have the response, and the second call to responseText() would return a null string.

I would suggest the the "solution" code:

String responseResult = request->responseText();
Serial.println(responseResult.c_str());

Would work just as well with:

String responseResult = request->responseText();
Serial.println(responseResult);

It really doesn't have anything to do with asyncHTTPrequest. It's work is done in the first line. The printf is overloaded and should work fine with either a String or char* argument.

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