QDataGridBase::Sort_Click PHP Method

    public function Sort_Click($strFormId, $strControlId, $strParameter)
    {
        $this->blnModified = true;
        if (strlen($strParameter)) {
            // Sorting
            $intColumnIndex = QType::Cast($strParameter, QType::Integer);
            $objColumn = $this->objColumnArray[$intColumnIndex];
            // First, reset pagination (if applicable)
            if ($this->objPaginator) {
                $this->PageNumber = 1;
            }
            // First, make sure the Column is Sortable
            if ($objColumn->OrderByClause) {
                // It is
                // Are we currently sorting by this column?
                if ($this->intSortColumnIndex == $intColumnIndex) {
                    // Yes we are currently sorting by this column
                    // In Reverse?
                    if ($this->intSortDirection == 1) {
                        // Yep -- unreverse the sort
                        $this->intSortDirection = 0;
                    } else {
                        // Nope -- can we reverse?
                        if ($objColumn->ReverseOrderByClause) {
                            $this->intSortDirection = 1;
                        }
                    }
                } else {
                    // Nope -- so let's set it to this column
                    $this->intSortColumnIndex = $intColumnIndex;
                    $this->intSortDirection = $objColumn->DefaultSortDirection;
                }
            } else {
                // It isn't -- clear all sort properties
                $this->intSortDirection = 0;
                $this->intSortColumnIndex = -1;
            }
        }
    }