cannot convert 'String' to 'char*' for argument '1' to 'int sprintf(char*, const

Projects Programming
1

I have this error:

cannot convert 'String' to 'char*' for argument '1' to 'int sprintf(char*, const char*, ...)'

2

The compiler told you what is wrong with your incomplete and badly-posted code.

3

mydata is a String and not...

char mydata[...];