Data Validation

Providing help and feedback to the user

Excel allows you to use the Helper program (the annoying little paper clip, or cat, or Einstein etc.) to display messages dependant on what the user has entered into a cell. It can also check to make sure the correct sort of data has been entered, e.g. decimal numbers or text etc.

To use Data Validation, Select the cell to be validated (the first answer cell) and Select Data>Validation... from the menu. Under Settings, set the data type that will be allowed in the cell (in this case, a decimal value). You can then decide on the criteria: I've set it to be triggered by values which are between 3 and 4. Make sure that Blank Cells are ignored.

The Input Message is for information which is to be displayed when the cell is Selected. It may be more useful to set the Error Alert to produce the information after the data has been entered into the cell.

There are three Error Alert styles to choose from:

• Information displays the information you enter in a box which has OK and Cancel buttons;
• Warning displays the information you enter in a box which has Continue?, Yes, No and Cancel buttons;
• Stop displays the information you enter in a box which has Retry and Cancel buttons.

Try to provide meaningful information in your messages which will help the user. If you don't enter a title, the box will be displayed with Microsoft Excel as the default title. The message box can contain a maximum of 225 characters.