Sets the control's value to the supplied formula
BOOL SetFormula( const char* pszFormula, BOOL bA1 = TRUE );
A pointer to a null-terminated string containing a formula.
Flag denoting whether the formula is in A1-style or R1C1 style. TRUE indicates that all references are in A1 form; FALSE that they are in R1C1 form.
Returns TRUE if the call is successful; FALSE if the call fails. The call may fail if the formula is invalid.
Sets the value displayed in the control.