Control Choice - Do you use checkboxes instead of multi-select dropdowns?

For multiple items selection, **multi-select dropdown listboxes** have a number of behavioral quirks that make it difficult for users to get used to them:

- They require users to know that you select more than one entry by holding down the **Ctrl** key
- They lose all selections if you click in the wrong place
- You can't tell if a Listbox is single-select or multi-select at first glance
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    figure: 'Bad Example - ListBoxes are impractical for multiple choices',
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  src="/uploads/rules/control-choice-do-you-use-checked-list-boxes-instead-of-multi-select-list-boxes/multiple-select-dropdown-bad.jpg"
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**Note:** It is OK and recommended to use dropdown lists for single item selection, when there is no more than 10 options.

**Checked Listboxes** are the ideal alternative for multiple items selections. They're much more pleasant to use and are a good deal more intuitive - compare to the list above. Checked Listboxes tell users immediately that they have the ability choose multiple options.

- In ASP.NET, use **System.Web.UI.WebControls.CheckBoxList**. If you're having problems with there being too many items in the list, use a **scrolling div**
- In Windows Forms, use **System.Windows.Forms.CheckedListBox**

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We have a program called [SSW Code Auditor](https://www.ssw.com.au/ssw/codeauditor/) to check for this rule.