String to char array conversion In my project I need to convert a string to a char array. From various examples I concluded that toCharArray() will convert a string to a char array. But I failed to do so. The error is:


  'a' does not name a type


The code I am using is:

String a = "45317";
char b[6];
a.toCharArray(b,6);


Resources are https://www.arduino.cc/en/Reference/StringToCharArray and http://forum.arduino.cc/index.php?topic=199362.0
If you're trying to use a method of a in the global scope, that's doomed to failure. You can only call methods within functions.

If all you want is a char array with "45317" in it then just use:

char *b = "45317";


If you want to convert a string that is built at runtime into a char array, then your current method is correct - you just have to do it in the right place.