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Peter's Professional Validation
Evaluating Data Entry Fields

Peter's Professional Validation has the most extensive set of tools for validating data entry fields on any platform. There's so much more to validation than just having 27 validators controls. Each of those validators needs additional rules to handle all the real-world cases that ASP.NET users encounter.

A fundamental goal of Peter's Data Entry Suite is to reduce the custom code that you have to write.

Validator Controls

Peter's Professional Validation includes 27 Validator controls. The heart of each of these validators is the "Condition", an object that determines how to evaluate data on the page. The Condition object is portable. You will use it in the MultiConditionValidator and Enabler property, further reducing your need to write custom code.
  • RequiredTextValidator – Tests if a field's textual value is "blank" or not. You can define what text represents "blank". It is similar to Microsoft's RequiredFieldValidator.
  • RequiredListValidator – Tests if a ListBox, DropDownList, RadioButtonList, or CheckBoxList is "blank". You can define what selected item represents "blank".
  • MultipleRequiredControlsValidator - Tests several fields to determine how many have been filled in (not “blank”). It supports these rules: All, All or none, Only one, At least one, and a range.
  • DataTypeCheckValidator – Tests a field's textual value to confirm it represents a particular data type. It is similar to Microsoft's CompareValidator when the Operator property is "DataTypeCheck".
  • CompareToValueValidator – Tests a field's textual value against another value that you supply. You determine the data type of the values and the operator to compare the two. It is similar to Microsoft's CompareValidator when the ValueToCompare property is used.
  • CompareTwoFieldsValidator – Tests the values of two fields to each other. You select the operator that is used in the comparison and the data type. It is similar to Microsoft's CompareValidator when the ControlToCompare property is used.
  • DifferenceValidator – Evaluates two TextBox fields to determine if the difference between their two values is a certain number apart from each other. You select the data type (including dates), a value to compare and the operator. For example, test that two dates are less than 60 days apart.
  • RangeValidator – Tests a field's textual value is between a minimum and maximum value. You determine the data type of the values. It is similar to Microsoft's RangeValidator.
  • RegexValidator – Tests a field's textual value against a regular expression. It is similar to Microsoft's RegularExpressionValidator with the addition of properties to control the RegEx options: Multiline and IgnoreCase. It also has a caching feature to avoid the overhead of compiling the regular expression text into the RegEx object with each request.

    Design mode predefines more than 20 expressions including:
    • U.S. and international phone numbers
    • Several types of URLs
    • U.S. and other postal codes
    • Credit Cards with and without spaces
    • U.S. Social Security Number
    The Properties Editor for this validator includes a tool to test your Regular Expressions.
  • CompareToStringsValidator – Tests a field's textual value against a list of strings. If the text matches one of the strings, it is valid. For example, you want to have the user type an answer of "Bird", "Cat" or "Dog". It allows you to use a datasource (DataSet, DataTable, ArrayList) to populate the list of strings.
  • EmailAddressValidator – Reviews the pattern of text for an email address to make sure it confirms with standards. In addition, you can hook it up to Advanced Intellect's aspNetMX validation engine for more thorough validation. Click here for a demo.
  • CreditCardNumberValidator – Confirms that the pattern is valid for credit card numbers. Its evaluation rules confirm that the text is all digits, follows Luhn's formula, and if desired, matches specific brands of credit cards. It does not provide credit card number approval software.
  • ABARoutingNumberValidator – Confirms that the pattern is valid for ABA routing numbers such as check routing numbers. It confirms that the text is always 9 digits that are confirmed with a checksum rule defined by the American Bankers Association.
  • CharacterValidator - Tests a field's textual value to confirm that each character is in a character set that you specify. For example, you require a password to be letters, digits, and underscores only. This validator doesn't care about the order or pattern of characters.
  • TextLengthValidator – Evaluates the number of characters in a TextBox against a minimum and/or maximum. It can evaluate the number of characters combined in two TextBoxes, if desired.
  • WordCountValidator – Evaluates the number of words in a TextBox against a minimum and/or maximum. It can evaluate the number of words combined in two TextBoxes, if desired.
  • CheckStateValidator – Evaluates the mark within a checkbox or radio button.
  • SelectedIndexValidator – Evaluates the selected index of a ListBox, DropDownList, RadioButtonList, or CheckBoxList.
  • SelectedIndexRangesValidator - Evaluates the selected index of a ListBox, DropDownList, RadioButtonList, or CheckBoxList against a list of ranges. This way, you can have several valid selected indexes.
  • CountSelectionsValidator – Evaluates CheckBoxLists and multi-selection ListBoxes to determine how many items are selected. You can establish a minimum and maximum.
  • ListSizeValidator - Evaluates the number of items shown in a listbox or dropdownlist. Typically used when the user interface allows adding and removing items in a list, where you have a minimum or maximum for the number of items shown.
  • CountTrueConditionsValidator – Lets you define a list of conditions for a number of fields. Evaluates how many of those conditions are true and compares them to a minimum and maximum. A common usage is with a list of checkboxes (not using a CheckBoxList) to emulate the CountSelectionsValidator.
  • DuplicateEntryValidator - Determines if three or more TextBoxes, DropDownLists, or ListBoxes have a matching value. It reports an error when a duplicate is found.
  • UnwantedWordsValidator – Compares a list of words to the text. It reports an error when any of the words is found within the text. Use it to block bad language and other words that are inappropriate. It has rules to catch words where letters are separated by other characters like, if you are looking for "jerk", you will find it in "j*e!r$k".
  • CustomValidator – Build your own validator's condition. It is like Microsoft's CustomValidator, where you associate an event handler to handle server side validation and the name of a JavaScript function that you supply for client-side validation.
  • IgnoreConditionValidator – This validator has no condition of its own. It is used to hold an error message that you manually show by setting its IsValid property false in some program code. While the CustomValidator forces you to move some of your validation logic into its own event handler, this validator lets you keep all of your logic in one common area.

The MultiConditionValidator Control

Many times, a rule for validation really needs to be built from multiple conditions and fields. For example, you want one validator that combines the RequiredTextValidator with the DataTypeCheckValidator. Or you have three TextBoxes and want one error message to report any possible errors found between them.

DES provides the MultiConditionValidator to combine the power of Condition objects taken from other validators into one validator. This single Validator often replaces the need for the writing custom code with the CustomValidator and allows you to benefit from all the multibrowser compatible client-side code already written for validators.

The MultiConditionValidator allows you to build complex boolean expressions like:
(Condition1 OR (Condition2 AND Condition3) OR (NOT (Condition4 AND Condition5 AND Condition6)))

It includes a powerful design mode interface to help build the rules of your new condition.

Validation Groups

Often pages have separate data entry areas with their own submit buttons and should only validate the fields associated with the submit button that is clicked.

DES supports Validation Groups, which lets you mark each validator and submit button with a group name. The submit button will only validate those members of its own group.

The Enabler Property

Each validator has an Enabler Condition. This allows the validator to turn itself on and off based on any condition you want. When off, the validator will not attempt to evaluate the fields. For example, you have a TextBox whose RequiredTextValidator should only validate when a checkbox is marked.

Often you will want to disable the validator when the data entry field being evaluated is invisible, disabled, readonly or have some other attribute. DES supplies these specialized conditions for use in the Enabler Condition: VisibleCondition, EnabledCondition, ReadOnlyCondition, ClassNameCondition, and CompareToValueCondition. This last condition can evaluate almost any DHTML/DOM attribute or style on the data entry field.

The Enabler Condition can use the powerful MultiCondition (the condition from the MultiConditionValidator) to build complex boolean expressions such as: "enable this validator when the TextBox is visible AND enabled AND the CheckBox1 is checked".

Data Types

Any validator that translates text into a particular data type supports a customizable list of data types. The data types that come with DES are:
  • String
  • String-Case Insensitive
  • Integer
  • Double
  • Date
  • Currency
  • Currency with Symbol
  • Percent
  • Percent with Symbol
  • Positive Integer
  • Positive Double
  • Positive Currency
  • Positive Currency with Symbol
Peter's Date and Time module users also get:
  • Extended Date - on the DateTextBox with support for abbreviated and long date formats.
  • Time Of Day - on the TimeOfDayTextBox
  • Duration - on the DurationTextBox
You can define additional data types.

Data types support localization.

More Features on Validation Controls

  • By default, the validator evaluates its condition when the user changes a field and when they submit. You can turn off either of these actions.
    • When the validator does not fire on submission, you can use the validator as a warning message since it will not stop the user from submitting the page. For example, "Values above 100 may generate a page that is too large for your printer." or "Dates after March 30 cannot be guaranteed. Call us."
    • When the validator does not fire when the field changes, you can show errors only when the user submits. They can still show next to the field or only in the ValidatorSummary control.
  • All conditions have a "Not" property. This allows you to reverse the logic that makes a condition true. For example, when this property is true on a RequiredTextValidator, the TextBox is valid when it is blank. This property will frequently be used when building complex Boolean expressions with the MultiConditionValidator.
  • All conditions that evaluate against a TextBox have a "Trim" property to determine if you want it to trim the text prior to evaluating the condition.
Peter's Data Entry Suite gives you feature rich and interactive data entry web forms with over 100 web controls.
Start with better controls. Finish with better sites.
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Related products: Peter's Data Entry Suite  | Peter's Business Logic Driven UI ("BLD")  | Peter's Professional Validation  | Peter's More Validators
Peter's Date and Time  | Peter's TextBoxes  | Peter's Interactive Pages  | Peter's Input Security