System.Windows.Forms.CustomTabControl.ShowTab C# (CSharp) Method

        public void ShowTab(TabPage page)
        {
            if (page != null){
                if (this._TabPages != null){
                    if (!this.TabPages.Contains(page)
                        && this._TabPages.Contains(page)){

                        //	Get insert point from backup of pages
                        int pageIndex = this._TabPages.IndexOf(page);
                        if (pageIndex > 0){
                            int start = pageIndex -1;

                            //	Check for presence of earlier pages in the visible tabs
                            for (int index = start; index >= 0; index--){
                                if (this.TabPages.Contains(this._TabPages[index])){

                                    //	Set insert point to the right of the last present tab
                                    pageIndex = this.TabPages.IndexOf(this._TabPages[index]) + 1;
                                    break;
                                }
                            }
                        }

                        //	Insert the page, or add to the end
                        if  ((pageIndex >= 0) && (pageIndex < this.TabPages.Count)){
                            this.TabPages.Insert(pageIndex, page);
                        } else {
                            this.TabPages.Add(page);
                        }
                    }
                } else {

                    //	If the page is not found at all then just add it
                    if (!this.TabPages.Contains(page)){
                        this.TabPages.Add(page);
                    }
                }
            }
        }