JVCL Help:TJvValidators

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Class Hierarchy[edit]

TJvComponent
TJvValidators
run\JvValidators.pas


Summary[edit]

Maintains a list of TJvBaseValidator or descendants.

run\JvValidators.pas


Pascal[edit]

 run\JvValidators.pas
 TJvValidators = class(TJvComponent);


Description[edit]

  1. JVCLInfo

Use validators to handle the validation logic in your application. Traditionally, developers have been forced to write validation logic for user input in their applications. With validators, the whole process can be set up at design time and many times even without writing more than a single line of code.
When validators have been set up, a single call to the Validate method checks all validators which in turn perform their validation according to their settings. If any of the validations fails, there are several options available to handle the failure. Here are the options available:

  • Use an ErrorIndicator. An ErrorIndicator can display an error icon next to the control thatfailed the validation. Moving the mouse pointer over the error icon, displays the error message in a hint window.
  • Use a ValidationSummary. A ValidationSummary collects all error messages and puts them into a string list. You can display this list of errors any way you like. For example, you can easily display all active errors in a label on the form.
  • Use the OnValidateFailed event. With the OnValidateFailed event, you can do any custom error handling of your choice.
  • Create a custom method of retrieving failed validations.

You can even use all of the options at the same time or in different combinations.

run\JvValidators.pas


See Also[edit]

TJvBaseValidator, TJvValidationSummary

run\JvValidators.pas


About[edit]

Navigation[edit]

run\JvValidators.pas



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