wpf 窗体加载于tabControl_SelectionChanged时间触发顺序

我有一个窗体 里面有一个tabControl控件。并写了tabControl_SelectionChanged事件。
代码如下：

/// <summary>

        /// 选择选项卡

        /// </summary>

        /// <param name="sender"></param>

        /// <param name="e"></param>

        public event RoutedEventHandler tabChanged;

        private void tabControl1_SelectionChanged(object sender, SelectionChangedEventArgs e)

        {

            if (e.Source is TabControl)

            {

                int tab = this.tabControl1.SelectedIndex;

                TabIniti(tab);

            }

            

        }

public void TabIniti(int tab)

        {

            switch (tab)

            {

                case 0:

                    this.cbbm.Visibility = Visibility.Collapsed;

                    this.sjxx.Visibility = Visibility.Collapsed;

                    this.xxxx.Visibility = Visibility.Visible;

                    break;

                case 1:

                    this.cbbm.Visibility = Visibility.Visible;

                    this.sjxx.Visibility = Visibility.Collapsed;

                    this.xxxx.Visibility = Visibility.Collapsed;

                    break;

                case 2:

                    this.cbbm.Visibility = Visibility.Collapsed;

                    this.sjxx.Visibility = Visibility.Visible;

                    this.xxxx.Visibility = Visibility.Collapsed;

                    break;

            }

        }

问题来了，插入断点，窗体在加载的时候就会直接跳进tabControl_SelectionChanged事件，，，我现在能想到的只能是加个全局参数去判断是否第一次加载。
有没有更好的方法去判断，第一次加载窗体的时候不触发tabControl_SelectionChanged事件啊？
在线等，，，