Visual C# | Validating forms exercise | Validating name and age entered

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The answer to the exercise will be included and explained if you attend the relevant Wise Owl course (sadly, only in the UK for now).

Software ==> Visual C#  (79 exercises)
Version ==>
Topic ==> Validating forms  (6 exercises)
Level ==> Relatively easy
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Add the existing form shown above to your project - you should see this:

Visual C Sharp 2005 exercise - Validating forms (image 1)

Initially there is no validation applied

Add code to the Validating event of the txtName textbox, so that if the user leaves the length of this textbox as zero you see an error message:

Visual C Sharp 2005 exercise - Validating forms (image 2)

This is what you should see if you leave the name blank

Now do the same for the txtAge field, but this time check that it is a whole number:

Visual C Sharp 2005 exercise - Validating forms (image 3)

The age must be filled in, and must be a whole number

The easiest way to do this is with a try ... catch ... clause, within which you attempt to convert the age filled in into an integer.

Finally, add code to the Age field's Validated event so that the age is increased by 10 years after it has been checked:

Visual C Sharp 2005 exercise - Validating forms (image 4)

Acknowledge the fact that no one tells the truth about their age ...

You should now see that the Validated event fires whether you change the value in their Age text box or not.  How might you stop your age increasing by 10 years every time a user leaves the Age text box?

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