9. Checking Input Data with Validators

In this chapter, we will provide an overview of standard ZF validators that can be used with your forms, and will also show how to write a custom validator. A validator is a class designed to take some input data, check it for correctness, and return a boolean result telling whether the data is correct (and error messages if the data has some errors).

In general, you even can use validators outside forms to process an arbitrary data. For example, validators may be used in a controller action to ensure that data passed as GET and/or POST variables is secure and conform to certain format.

ZF3 components covered in this chapter:

• 9.1. About Validators
  • 9.1.1. ValidatorInterface
• 9.2. Standard Validators Overview
• 9.3. Validator Behaviour in Case of Invalid or Unacceptable Data
• 9.4. Instantiating a Validator
  • 9.4.1. Method 1. Manual Instantiation of a Validator
  • 9.4.2. Method 2. Using StaticValidator Wrapper
  • 9.4.3. Method 3. Using an Array Configuration
• 9.5. About Validator Plugin Manager
• 9.6. Validator Usage Examples
  • 9.6.1. Validators for Checking Value Conformance to Certain Format
    • 9.6.1.1. Ip Validator
    • 9.6.1.2. Hostname Validator
    • 9.6.1.3. Uri Validator
    • 9.6.1.4. Date Validator
    • 9.6.1.5. Regex Validator
  • 9.6.2. Validators for Checking if a Numerical Value Lies in a Given Range
    • 9.6.2.1. NotEmpty Validator
    • 9.6.2.2. Between Validator
    • 9.6.2.3. InArray Validator
    • 9.6.2.4. StringLength Validator
  • 9.6.3. Organizing Validators in a Chain
  • 9.6.4. Custom Validation with the Callback Validator
    • 9.6.4.1. Example
• 9.7. Writing Own Validator
  • 9.7.1. Using the PhoneValidator Class
• 9.8. Using Filters & Validators Outside a Form
• 9.9. Summary