Putting validators to work is quite simple. There are several methods for adding and manipulating validators:

• isValid($files = null): Checks the specified files using all validators. $files may be either a real filename, the element's name or the name of the temporary file.

• addValidator($validator, $breakChainOnFailure, $options = null, $files = null): Adds the specified validator to the validator stack (optionally only to the file(s) specified). $validator may be either an actual validator instance or a short name specifying the validator type (e.g., 'Count').

• addValidators(array $validators, $files = null): Adds the specified validators to the stack of validators. Each entry may be either a validator type/options pair or an array with the key 'validator' specifying the validator. All other options will be considered validator options for instantiation.

• setValidators(array $validators, $files = null): Overwrites any existing validators with the validators specified. The validators should follow the syntax for addValidators().

• hasValidator($name): Indicates whether a validator has been registered.

• getValidator($name): Returns a previously registered validator.

• getValidators($files = null): Returns registered validators. If $files is specified, returns validators for that particular file or set of files.

• removeValidator($name): Removes a previously registered validator.

• clearValidators(): Clears all registered validators.

Normally, you should use the addValidators() method, which can be called multiple times.

Note: Note that setting the same validator multiple times is allowed, but doing so can lead to issues when using different options for the same validator.

Last but not least, you can simply check the files using isValid().

Note: Note that isValid() will be called automatically when you receive the files and have not called it previously.

When validation has failed it is a good idea to get information about the problems found. To get this information, you can use the methods getMessages() which returns all validation messages as array, getErrors() which returns all error codes, and hasErrors() which returns TRUE as soon as a validation error has been found.

The Count validator checks for the number of files which are provided. It supports the following option keys:

• min: Sets the minimum number of files to transfer.

  Note: When using this option you must give the minimum number of files when calling this validator the first time; otherwise you will get an error in return.
  

  With this option you can define the minimum number of files you expect to receive.

• max: Sets the maximum number of files to transfer.

  With this option you can limit the number of files which are accepted but also detect a possible attack when more files are given than defined in your form.

If you initiate this validator with a string or integer, the value will be used as max. Or you can also use the methods setMin() and setMax() to set both options afterwards and getMin() and getMax() to retrieve the actual set values.

Note: Note that this validator stores the number of checked files internally. The file which exceeds the maximum will be returned as error.

The Crc32 validator checks the content of a transferred file by hashing it. This validator uses the hash extension from PHP with the crc32 algorithm. It supports the following options:

• *: Sets any key or use a numeric array. The values will be used as hash to validate against.

  You can set multiple hashes by using different keys. Each will be checked and the validation will fail only if all values fail.

The ExcludeExtension validator checks the file extension of the specified files. It supports the following options:

• *: Sets any key or use a numeric array. The values will be used to check whether the given file does not use this file extension.

• case: Sets a boolean indicating whether validation should be case-sensitive. The default is not case sensitive. Note that this key can be applied to for all available extensions.

This validator accepts multiple extensions, either as a comma-delimited string, or as an array. You may also use the methods setExtension(), addExtension(), and getExtension() to set and retrieve extensions.

In some cases it is useful to match in a case-sensitive fashion. So the constructor allows a second parameter called $case which, if set to TRUE, validates the extension by comparing it with the specified values in a case-sensitive fashion.

Note: Note that this validator only checks the file extension. It does not check the file's MIME type.

The ExcludeMimeType validator checks the MIME type of transferred files. It supports the following options:

• *: Sets any key individually or use a numeric array. Sets the MIME type to validate against.

  With this option you can define the MIME type of files that are not to be accepted.

• headerCheck: If set to TRUE this option will check the HTTP Information for the file type when the fileInfo or mimeMagic extensions can not be found. The default value for this option is FALSE.

This validator accepts multiple MIME types, either as a comma-delimited string, or as an array. You may also use the methods setMimeType(), addMimeType(), and getMimeType() to set and retrieve the MIME types.

The above example shows that it is also possible to disallow groups of MIME types. For example, to disallow all images, just use 'image' as the MIME type. This can be used for all groups of MIME types like 'image', 'audio', 'video', 'text', etc.

Note: Note that disallowing groups of MIME types will disallow all members of this group even if this is not intentional. When you disallow 'image' you will disallow all types of images like 'image/jpeg' or 'image/vasa'. When you are not sure if you want to disallow all types, you should disallow only specific MIME types instead of complete groups.

The Exists validator checks for the existence of specified files. It supports the following options:

• *: Sets any key or use a numeric array to check if the specific file exists in the given directory.

This validator accepts multiple directories, either as a comma-delimited string, or as an array. You may also use the methods setDirectory(), addDirectory(), and getDirectory() to set and retrieve directories.

Note: Note that this validator checks whether the specified file exists in all of the given directories. The validation will fail if the file does not exist in any of the given directories.

The Extension validator checks the file extension of the specified files. It supports the following options:

• *: Sets any key or use a numeric array to check whether the specified file has this file extension.

• case: Sets whether validation should be done in a case-sensitive fashion. The default is no case sensitivity. Note the this key is used for all given extensions.

This validator accepts multiple extensions, either as a comma-delimited string, or as an array. You may also use the methods setExtension(), addExtension(), and getExtension() to set and retrieve extension values.

In some cases it is useful to test in a case-sensitive fashion. Therefore the constructor takes a second parameter $case, which, if set to TRUE, will validate the extension in a case-sensitive fashion.

Note: Note that this validator only checks the file extension. It does not check the file's MIME type.

The FilesSize validator checks for the aggregate size of all transferred files. It supports the following options:

• min: Sets the minimum aggregate file size. This option defines the minimum aggregate file size to be transferred.

• max: Sets the maximum aggregate file size.

  This option limits the aggregate file size of all transferred files, but not the file size of individual files.

• bytestring: Defines whether a failure is to return a user-friendly number or the plain file size.

  This option defines whether the user sees '10864' or '10MB'. The default value is TRUE, so '10MB' is returned if you did not specify otherwise.

You can initialize this validator with a string, which will then be used to set the max option. You can also use the methods setMin() and setMax() to set both options after construction, along with getMin() and getMax() to retrieve the values that have been set previously.

The size itself is also accepted in SI notation as handled by most operating systems. That is, instead of specifying 20000 bytes, 20kB may be given. All file sizes are converted using 1024 as the base value. The following Units are accepted: kB, MB, GB, TB, PB and EB. Note that 1kB is equal to 1024 bytes, 1MB is equal to 1024kB, and so on.

Note: Note that this validator internally stores the file size of checked files. The file which exceeds the size will be returned as an error.

The ImageSize validator checks the size of image files. It supports the following options:

• minheight: Sets the minimum image height.

• maxheight: Sets the maximum image height.

• minwidth: Sets the minimum image width.

• maxwidth: Sets the maximum image width.

The methods setImageMin() and setImageMax() also set both minimum and maximum values, while the methods getMin() and getMax() return the currently set values.

For your convenience there are also the setImageWidth() and setImageHeight() methods, which set the minimum and maximum height and width of the image file. They, too, have corresponding getImageWidth() and getImageHeight() methods to retrieve the currently set values.

To bypass validation of a particular dimension, the relevent option simply should not be set.

The IsCompressed validator checks if a transferred file is a compressed archive, such as zip or arc. This validator is based on the MimeType validator and supports the same methods and options. You may also limit this validator to particular compression types with the methods described there.

Note: Note that there is no check if you set a MIME type that is not a archive. For example, it would be possible to define gif files to be accepted by this validator. Using the 'MimeType' validator for files which are not archived will result in more readable code.

The IsImage validator checks if a transferred file is a image file, such as gif or jpeg. This validator is based on the MimeType validator and supports the same methods and options. You can limit this validator to particular image types with the methods described there.

Note: Note that there is no check if you set a MIME type that is not an image. For example, it would be possible to define zip files to be accepted by this validator. Using the 'MimeType' validator for files which are not images will result in more readable code.

The Hash validator checks the content of a transferred file by hashing it. This validator uses the hash extension from PHP. It supports the following options:

• *: Takes any key or use a numeric array. Sets the hash to validate against.

  You can set multiple hashes by passing them as an array. Each file is checked, and the validation will fail only if all files fail validation.

• algorithm: Sets the algorithm to use for hashing the content.

  You can set multiple algorithm by calling the addHash() method multiple times.

Note: This validator supports about 34 different hash algorithms. The most common include 'crc32', 'md5' and 'sha1'. A comprehesive list of supports hash algorithms can be found at the » hash_algos method on the » php.net site.

The Md5 validator checks the content of a transferred file by hashing it. This validator uses the hash extension for PHP with the md5 algorithm. It supports the following options:

• *: Takes any key or use a numeric array.

  You can set multiple hashes by passing them as an array. Each file is checked, and the validation will fail only if all files fail validation.

The MimeType validator checks the MIME type of transferred files. It supports the following options:

• *: Sets any key or use a numeric array. Sets the MIME type to validate against.

  Defines the MIME type of files to be accepted.

• headerCheck: If set to TRUE this option will check the HTTP Information for the file type when the fileInfo or mimeMagic extensions can not be found. The default value for this option is FALSE.

• magicfile: The magicfile to be used.

  With this option you can define which magicfile to use. When it's not set or empty, the MAGIC constant will be used instead. This option is available since Zend Framework 1.7.1.

This validator accepts multiple MIME type, either as a comma-delimited string, or as an array. You may also use the methods setMimeType(), addMimeType(), and getMimeType() to set and retrieve MIME type.

You can also set the magicfile which shall be used by fileinfo with the 'magicfile' option. Additionally there are convenient setMagicFile() and getMagicFile() methods which allow later setting and retrieving of the magicfile parameter. This methods are available since Zend Framework 1.7.1.

The above example shows that it is also possible to limit the accepted MIME type to a group of MIME types. To allow all images just use 'image' as MIME type. This can be used for all groups of MIME types like 'image', 'audio', 'video', 'text, and so on.

Note: Note that allowing groups of MIME types will accept all members of this group even if your application does not support them. When you allow 'image' you will also get 'image/xpixmap' or 'image/vasa' which could be problematic. When you are not sure if your application supports all types you should better allow only defined MIME types instead of the complete group.

Note: This component will use the FileInfo extension if it is available. If it's not, it will degrade to the mime_content_type() function. And if the function call fails it will use the MIME type which is given by HTTP.
You should be aware of possible security problems when you have whether FileInfo nor mime_content_type() available. The MIME type given by HTTP is not secure and can be easily manipulated.

The NotExists validator checks for the existence of the provided files. It supports the following options:

• *: Set any key or use a numeric array. Checks whether the file exists in the given directory.

This validator accepts multiple directories either as a comma-delimited string, or as an array. You may also use the methods setDirectory(), addDirectory(), and getDirectory() to set and retrieve directories.

Note: Note that this validator checks if the file does not exist in all of the provided directories. The validation will fail if the file does exist in any of the given directories.

The Sha1 validator checks the content of a transferred file by hashing it. This validator uses the hash extension for PHP with the sha1 algorithm. It supports the following options:

• *: Takes any key or use a numeric array.

  You can set multiple hashes by passing them as an array. Each file is checked, and the validation will fail only if all files fail validation.

The Size validator checks for the size of a single file. It supports the following options:

• min: Sets the minimum file size.

• max: Sets the maximum file size.

• bytestring: Defines whether a failure is returned with a user-friendly number, or with the plain file size.

  With this option you can define if the user gets '10864' or '10MB'. Default value is TRUE which returns '10MB'.

You can initialize this validator with a string, which will then be used to set the max option. You can also use the methods setMin() and setMax() to set both options after construction, along with getMin() and getMax() to retrieve the values that have been set previously.

The size itself is also accepted in SI notation as handled by most operating systems. That is, instead of specifying 20000 bytes, 20kB may be given. All file sizes are converted using 1024 as the base value. The following Units are accepted: kB, MB, GB, TB, PB and EB. Note that 1kB is equal to 1024 bytes, 1MB is equal to 1024kB, and so on.

The WordCount validator checks for the number of words within provided files. It supports the following option keys:

• min: Sets the minimum number of words to be found.

• max: Sets the maximum number of words to be found.

If you initiate this validator with a string or integer, the value will be used as max. Or you can also use the methods setMin() and setMax() to set both options afterwards and getMin() and getMax() to retrieve the actual set values.