正在獲取comboBox1.SelectedValue

Question

private void comboBox1_SelectedIndexChanged(object sender, EventArgs e) 
    { 
     switchItem(); 
    } 
private void switchItem() 
     { 
      var content = richTextBox1; 
      switch (comboBox1.SelectedValue.ToString()) 
      { 
       case "Fruit": 
        content.Text = "Apple"; 
        break; 
       default: 
        content.Rtf = "Not Selected"; 
        break; 
      } 
     } 

正如您所看到的，我試圖獲取comboBox1的SelectedValue，並且此object reference not set to an instance of an object錯誤出現。我該怎麼辦？

Answer 1

也許你正在尋找SelectedItem而不是SelectedValue

錯誤object reference not set to an instance of an object意味着SelectedValue是null