How to split a string into substring Arduino I'm about identify myself stupid, howcome I couldn' t figure out how to split a string into substring using arduino, even after 10 days of searching. The number is fact... So, As Mr.Arduino.cc says: string.substring() is just can be used as conditional phrase with loops like if. and there is no method such strtok() like in C can help me with this. So guys, I' m bagging you for help, please!

if (ks &gt; 255 * 60)
            {
                    vek.print("Bu yazı, ", 25, 0);
                    vek.printNumI(255*60, 25, 8);
                    vek.print("karakterd-", 25, 16);
                    vek.print("en uzun ol", 25, 24);
                    vek.print("dugundan", 25, 32);
                    vek.print("gosterlemz", 25, 40);
            }

for (byte i = 0; i &lt;= ss ; i ++)
            {
                    for (byte j = 0; j &lt;= 6; j++)
                    {
                            int ilk_kar = j * 10 + i * 60;
                            int son_kar = ilk_kar + 10;

                            String yaz=readString.strtok(ilk_kar,son_kar);

                            vek.print(yaz, 25, j);

                            if (analogRead(A5) == 1023)
                            {
                                    continue;
                            }
                            else
                            {
                                    break;
                            }
                    }
            }
    }
}


Error: sketch_aug22a.ino: In function ‘void loop()’:
sketch_aug22a.ino:83:56: error: ‘class String’ has no member named ‘strtok’

What am I supposed to do?

Thanks, already...
Import the string.h library by adding #include &lt;string.h&gt; on top of your sketch, in order to use the strtok() function.
Checkout the usage example of strtok() here: http://www.cplusplus.com/reference/cstring/strtok/?kw=strtok