tblAddColumn

int32_t __stdcall tblAddColumn(ITBL Table, BOOL32 Left, float Width);
void __stdcall tblDeleteCol(ITBL Table, uint32_t Col);

function tblAddColumn(const Table: ITBL; Left: LongBool; Width: Single): Integer; stdcall;
procedure tblDeleteCol(const Table: ITBL; Col: Cardinal); stdcall;

Purpose. Insert a new column at the left edge or append one at the right, growing every existing row with a new blank cell; or remove a specific column from every row.

Description. Real column insertion — was formerly "a fixed-column no-op" per an explicit inline comment ("G-17: real column insertion (was a fixed-column no-op)"). Left = True shifts every existing column's width and every row's existing cells one slot right before inserting the new blank column/cell at index 0; Left = False simply appends at the end. tblDeleteCol removes that column's width entry and, for every row, deletes that column's cell slot, decrementing NumCols — a real, complete column removal (not a mask/hide).

Parameters.

Return value. tblAddColumn: the new total column count. tblDeleteCol: none.

C# (P/Invoke)

public static extern int tblAddColumn(IntPtr Table, [MarshalAs(UnmanagedType.Bool)] bool Left, float Width);