Question

i have defined a value using

#define username "admin"

then i want to use the username in a char statement into sql as

const char *pSQL[1];
pSQL[1] = "update websrv_config set admin_id='" + username + "'";

but it seems that there is an error

error: invalid operands of types ‘const char [36]’ and ‘const char [6]’ to binary ‘operator+’

how can i overcome it?

Answer 1

Try this:

pSQL[0] = "update websrv_config set admin_id='"  username  "'";

In c++ array index starts with 0 so when you have decleared an array of length 1. The only index it can have is 0. Further, ‘+’ is not used for concatenation in c++.