Standard Filter ClassesZend Framework comes with a standard set of filters, which are ready for you to use. AlnumZend_Filter_Alnum is a filter which returns only alphabetic characters and digits. All other characters are supressed. Supported options for Zend_Filter_AlnumThe following options are supported for Zend_Filter_Alnum:
Basic usageSee the following example for the default behaviour of this filter.
The above example returns 'Thisismycontent123'. As you see all whitespaces and also the brackets are filtered.
Allow whitespacesZend_Filter_Alnum can also allow whitespaces. This can be usefull when you want to strip special chars from a text. See the following example:
The above example returns 'This is my content 123'. As you see only the brackets are filtered whereas the whitespaces are not touched. To change allowWhiteSpace afterwards you can use setAllowWhiteSpace() and getAllowWhiteSpace(). AlphaZend_Filter_Alpha is a filter which returns the string $value, removing all but alphabetic characters. This filter includes an option to also allow white space characters. Supported options for Zend_Filter_AlphaThe following options are supported for Zend_Filter_Alpha:
Basic usageA basic example of usage is below:
The above example returns 'Thisismycontent'. Notice that the whitespace characters and brackets are removed.
Allow whitespace charactersZend_Filter_Alpha can also allow whitespace characters. This can be useful when you want to strip special characters from a string. See the following example:
The above example returns 'This is my content '. Notice that the parenthesis, colon, and numbers have all been removed while the whitespace characters remain. To change allowWhiteSpace after instantiation the method setAllowWhiteSpace() may be used. To query the current value of allowWhiteSpace the method getAllowWhiteSpace() may be used. BaseNameZend_Filter_BaseName allows you to filter a string which contains the path to a file and it will return the base name of this file. Supported options for Zend_Filter_BaseNameThere are no additional options for Zend_Filter_BaseName. Basic usageA basic example of usage is below:
This will return 'filename'.
This will return 'filename.txt'. BooleanThis filter changes a given input to be a BOOLEAN value. This is often useful when working with databases or when processing form values. Supported options for Zend_Filter_BooleanThe following options are supported for Zend_Filter_Boolean:
Default behaviour for Zend_Filter_BooleanBy default, this filter works by casting the input to a BOOLEAN value; in other words, it operates in a similar fashion to calling (boolean) $value.
This means that without providing any configuration, Zend_Filter_Boolean accepts all input types and returns a BOOLEAN just as you would get by type casting to BOOLEAN. Changing behaviour for Zend_Filter_BooleanSometimes casting with (boolean) will not suffice. Zend_Filter_Boolean allows you to configure specific types to convert, as well as which to omit. The following types can be handled:
All other given values will return TRUE by default. There are several ways to select which of the above types are filtered. You can give one or multiple types and add them, you can give an array, you can use constants, or you can give a textual string. See the following examples:
You can also give an instance of Zend_Config to set the desired types. To set types after instantiation, use the setType() method. Localized booleansAs mentioned previously, Zend_Filter_Boolean can also recognise localized "yes" and "no" strings. This means that you can ask your customer in a form for "yes" or "no" within his native language and Zend_Filter_Boolean will convert the response to the appropriate boolean value. To set the desired locale, you can either use the locale option, or the method setLocale().
Disable castingSometimes it is necessary to recognise only TRUE or FALSE and return all other values without changes. Zend_Filter_Boolean allows you to do this by setting the casting option to FALSE. In this case Zend_Filter_Boolean will work as described in the following table, which shows which values return TRUE or FALSE. All other given values are returned without change when casting is set to FALSE
The following example shows the behaviour when changing the casting option:
CallbackThis filter allows you to use own methods in conjunction with Zend_Filter. You don't have to create a new filter when you already have a method which does the job. Supported options for Zend_Filter_CallbackThe following options are supported for Zend_Filter_Callback:
Basic usageThe usage of this filter is quite simple. Let's expect we want to create a filter which reverses a string.
As you can see it's really simple to use a callback to define a own filter. It is also possible to use a method, which is defined within a class, by giving an array as callback.
To get the actual set callback use getCallback() and to set another callback use setCallback().
Default parameters within a callbackIt is also possible to define default parameters, which are given to the called method as array when the filter is executed. This array will be concatenated with the value which will be filtered.
When you would call the above method definition manually it would look like this:
Compress and DecompressThese two filters are capable of compressing and decompressing strings, files, and directories. Supported options for Zend_Filter_Compress and Zend_Filter_DecompressThe following options are supported for Zend_Filter_Compress and Zend_Filter_Decompress:
Supported compression adaptersThe following compression formats are supported by their own adapter:
Each compression format has different capabilities as described below. All compression filters may be used in approximately the same ways, and differ primarily in the options available and the type of compression they offer (both algorithmically as well as string vs. file vs. directory) Generic handlingTo create a compression filter you need to select the compression format you want to use. The following description takes the Bz2 adapter. Details for all other adapters are described after this section. The two filters are basically identical, in that they utilize the same backends. Zend_Filter_Compress should be used when you wish to compress items, and Zend_Filter_Decompress should be used when you wish to decompress items. For instance, if we want to compress a string, we have to initiate Zend_Filter_Compress and indicate the desired adapter.
To use a different adapter, you simply specify it to the constructor. You may also provide an array of options or Zend_Config object. If you do, provide minimally the key "adapter", and then either the key "options" or "adapterOptions" (which should be an array of options to provide to the adapter on instantiation).
Almost the same usage is we want to decompress a string. We just have to use the decompression filter in this case.
To get the compressed string, we have to give the original string. The filtered value is the compressed version of the original string.
Decompression works the same way.
Creating an archiveCreating an archive file works almost the same as compressing a string. However, in this case we need an additional parameter which holds the name of the archive we want to create.
In the above example the uncompressed string is compressed, and is then written into the given archive file.
When you want to compress a file, then you must give the name of the file with its path.
You may also specify a directory instead of a filename. In this case the whole directory with all its files and subdirectories will be compressed into the archive.
Decompressing an archiveDecompressing an archive file works almost like compressing it. You must specify either the archive parameter, or give the filename of the archive when you decompress the file.
Some adapters support decompressing the archive into another subdirectory. In this case you can set the target parameter.
Bz2 AdapterThe Bz2 Adapter can compress and decompress:
This adapter makes use of PHP's Bz2 extension. To customize compression, this adapter supports the following options:
All options can be set at instantiation or by using a related method. For example, the related methods for 'Blocksize' are getBlocksize() and setBlocksize(). You can also use the setOptions() method which accepts all options as array. Gz AdapterThe Gz Adapter can compress and decompress:
This adapter makes use of PHP's Zlib extension. To customize the compression this adapter supports the following options:
All options can be set at initiation or by using a related method. For example, the related methods for 'Level' are getLevel() and setLevel(). You can also use the setOptions() method which accepts all options as array. Lzf AdapterThe Lzf Adapter can compress and decompress:
This adapter makes use of PHP's Lzf extension. There are no options available to customize this adapter. Rar AdapterThe Rar Adapter can compress and decompress:
This adapter makes use of PHP's Rar extension.
To customize the compression this adapter supports the following options:
All options can be set at instantiation or by using a related method. For example, the related methods for 'Target' are getTarget() and setTarget(). You can also use the setOptions() method which accepts all options as array. Tar AdapterThe Tar Adapter can compress and decompress:
This adapter makes use of PEAR's Archive_Tar component. To customize the compression this adapter supports the following options:
All options can be set at instantiation or by using a related method. For example, the related methods for 'Target' are getTarget() and setTarget(). You can also use the setOptions() method which accepts all options as array.
Zip AdapterThe Zip Adapter can compress and decompress:
This adapter makes use of PHP's Zip extension. To customize the compression this adapter supports the following options:
All options can be set at instantiation or by using a related method. For example, the related methods for 'Target' are getTarget() and setTarget(). You can also use the setOptions() method which accepts all options as array. DigitsReturns the string $value, removing all but digits. Supported options for Zend_Filter_DigitsThere are no additional options for Zend_Filter_Digits. Basic usageA basic example of usage is below:
This returns "2009".
This returns "5". DirGiven a string containing a path to a file, this function will return the name of the directory. Supported options for Zend_Filter_DirThere are no additional options for Zend_Filter_Dir. Basic usageA basic example of usage is below:
This returns "/etc".
This returns "C:/Temp". Encrypt and DecryptThese filters allow to encrypt and decrypt any given string. Therefor they make use of Adapters. Actually there are adapters for the Mcrypt and OpenSSL extensions from PHP. Supported options for Zend_Filter_Encrypt and Zend_Filter_DecryptThe following options are supported for Zend_Filter_Encrypt and Zend_Filter_Decrypt:
Adapter usageAs these two encryption methodologies work completely different, also the usage of the adapters differ. You have to select the adapter you want to use when initiating the filter.
To set another adapter you can also use setAdapter(), and the getAdapter() method to receive the actual set adapter.
Encryption with McryptWhen you have installed the Mcrypt extension you can use the Mcrypt adapter. If you provide a string instead of an array of options, this string will be used as key. You can get and set the encryption values also afterwards with the getEncryption() and setEncryption() methods.
You can get or set the encryption vector by calling getVector() and setVector(). A given string will be truncated or padded to the needed vector size of the used algorithm.
Decryption with McryptFor decrypting content which was previously encrypted with Mcrypt you need to have the options with which the encryption has been called. There is one eminent difference for you. When you did not provide a vector at encryption you need to get it after you encrypted the content by using the getVector() method on the encryption filter. Without the correct vector you will not be able to decrypt the content. As soon as you have provided all options decryption is as simple as encryption.
Encryption with OpenSSLWhen you have installed the OpenSSL extension you can use the OpenSSL adapter. You can get or set the public keys also afterwards with the getPublicKey() and setPublicKey() methods. The private key can also be get and set with the related getPrivateKey() and setPrivateKey() methods.
When you want to encode also the keys, then you have to provide a passphrase with the setPassphrase() method. When you want to decode content which was encoded with a passphrase you will not only need the public key, but also the passphrase to decode the encrypted key.
At last, when you use OpenSSL you need to give the receiver the encrypted content, the passphrase when have provided one, and the envelope keys for decryption. This means for you, that you have to get the envelope keys after the encryption with the getEnvelopeKey() method. So our complete example for encrypting content with OpenSSL look like this.
Simplified usage with OpensslAs seen before, you need to get the envelope key to be able to decrypt the previous encrypted value. This can be very annoying when you work with multiple values. To have a simplified usage you can set the package option to TRUE. The default value is FALSE.
Now the returned value contains the encrypted value and the envelope. You don't need to get them after the compression. But, and this is the negative aspect of this feature, the encrypted value can now only be decrypted by using Zend_Filter_Encrypt. Compressing the contentBased on the original value, the encrypted value can be a very large string. To reduce the value Zend_Filter_Encrypt allows the usage of compression. The compression option can eighter be set to the name of a compression adapter, or to an array which sets all wished options for the compression adapter.
Decryption with OpenSSLDecryption with OpenSSL is as simple as encryption. But you need to have all data from the person who encrypted the content. See the following example:
Optionally it could be necessary to provide the passphrase for decrypting the keys themself by using the setPassphrase() method.
At last, decode the content. Our complete example for decrypting the previously encrypted content looks like this.
HtmlEntitiesReturns the string $value, converting characters to their corresponding HTML entity equivalents where they exist. Supported options for Zend_Filter_HtmlEntitiesThe following options are supported for Zend_Filter_HtmlEntities:
Basic usageSee the following example for the default behaviour of this filter.
Quote StyleZend_Filter_HtmlEntities allows changing the quote style used. This can be useful when you want to leave double, single, or both types of quotes un-filtered. See the following example:
The above example returns A 'single' and "double". Notice that 'single' as well as "double" quotes are filtered.
The above example returns A 'single' and "double". Notice that "double" quotes are filtered while 'single' quotes are not altered.
The above example returns A 'single' and "double". Notice that neither "double" or 'single' quotes are altered. Helper MethodsTo change or retrieve the quotestyle after instantiation, the two methods setQuoteStyle() and getQuoteStyle() may be used respectively. setQuoteStyle() accepts one parameter $quoteStyle. The following constants are accepted: ENT_COMPAT, ENT_QUOTES, ENT_NOQUOTES To change or retrieve the charset after instantiation, the two methods setCharSet() and getCharSet() may be used respectively. setCharSet() accepts one parameter $charSet. See "http://php.net/htmlentities" for a list of supported character sets. To change or retrieve the doublequote option after instantiation, the two methods setDoubleQuote() and getDoubleQuote() may be used respectively. setDoubleQuote() accepts one boolean parameter $doubleQuote. IntZend_Filter_Int allows you to transform a sclar value which contains into an integer. Supported options for Zend_Filter_IntThere are no additional options for Zend_Filter_Int. Basic usageA basic example of usage is below:
This will return '-4'. LocalizedToNormalized and NormalizedToLocalizedThese two filters can change given localized input to it's normalized representation and reverse. They use in Background Zend_Locale to do this transformation for you. Supported options for Zend_Filter_LocalizedToNormalized and Zend_Filter_NormalizedToLocalizedThe following options are supported for Zend_Filter_LocalizedToNormalized and Zend_Filter_NormalizedToLocalized:
WorkflowNormalization allows your user to enter informations in his own language notation, and you can then store the normalized value into your database for example. Localization on the other hand allows you to display normalized informations in a localized manner to your user.
The following input types can be normalized and localized:
Any other input will be returned as is, without changing it.
Normalization for numbersAny given number like integer, float or real value, can be normalized. Note, that numbers in scientific notation, can actually not be handled by this filter. So how does this normalization work in detail for numbers:
Let's expect you have set the locale 'de' as application wide locale. Zend_Filter_LocalizedToNormalized will take the set locale and use it to detect which sort of input you gave. In our example it was a value with precision. Now the filter will return you the normalized representation for this value as string. You can also control how your normalized number has to look like. Therefor you can give all options which are also used by Zend_Locale_Format. For details about available options take a look into this Zend_Locale chapter. Below is a example with defined precision so you can see how options work:
Normalization for date and timeInput for date and time values can also be normalized. All given date and time values will be returned as array, where each date part is given within a own key.
Let's expect you have set the locale 'de' again. Now the input is automatically detected as date, and you will get a named array in return. Of course you can also control how your date input looks like with the date_format and the locale option.
Localization for numbersAny given number like integer, float or real value, can be localized. Note, that numbers in scientific notation, can actually not be handled by this filter. So how does localization work in detail for numbers:
Let's expect you have set the locale 'de' as application wide locale. Zend_Filter_NormalizedToLocalized will take the set locale and use it to detect which sort of output you want to have. In our example it was a value with precision. Now the filter will return you the localized representation for this value as string. You can also control how your localized number has to look like. Therefor you can give all options which are also used by Zend_Locale_Format. For details about how these options are used take a look into this Zend_Locale chapter. Below is a example with defined precision so you can see how options work:
Localization for date and timeNormalized for date and time values can also be localized. All given date and time values will be returned as string, with the format defined by the set locale.
Let's expect you have set the locale 'de' again. Now the input is automatically detected as date, and will be returned in the format defined by the locale 'de'. Of course you can also control how your date input looks like with the date_format, and the locale option.
NullThis filter will change the given input to be NULL if it meets specific criteria. This is often necessary when you work with databases and want to have a NULL value instead of a boolean or any other type. Supported options for Zend_Filter_NullThe following options are supported for Zend_Filter_Null:
Default behaviour for Zend_Filter_NullPer default this filter works like PHP's empty() method; in other words, if empty() returns a boolean TRUE, then a NULL value will be returned.
This means that without providing any configuration, Zend_Filter_Null will accept all input types and return NULL in the same cases as empty(). Any other value will be returned as is, without any changes. Changing behaviour for Zend_Filter_NullSometimes it's not enough to filter based on empty(). Therefor Zend_Filter_Null allows you to configure which type will be converted and which not. The following types can be handled:
There are several ways to select which of the above types are filtered. You can give one or multiple types and add them, you can give an array, you can use constants, or you can give a textual string. See the following examples:
You can also give an instance of Zend_Config to set the wished types. To set types afterwards use setType(). PregReplaceZend_Filter_PregReplace performs a search using regular expressions and replaces all found elements. Supported options for Zend_Filter_PregReplaceThe following options are supported for Zend_Filter_PregReplace:
Basic usageTo use this filter properly you must give two options: The option match has to be given to set the pattern which will be searched for. It can be a string for a single pattern, or an array of strings for multiple pattern. To set the pattern which will be used as replacement the option replace has to be used. It can be a string for a single pattern, or an array of strings for multiple pattern.
You can use getMatchPattern() and setMatchPattern() to set the matching pattern afterwards. To set the replacement pattern you can use getReplacement() and setReplacement().
For a more complex usage take a look into PHP's » PCRE Pattern Chapter. RealPathThis filter will resolve given links and pathnames and returns canonicalized absolute pathnames. Supported options for Zend_Filter_RealPathThe following options are supported for Zend_Filter_RealPath:
Basic usageFor any given link of pathname its absolute path will be returned. References to '/./', '/../' and extra '/' characters in the input path will be stripped. The resulting path will not have any symbolic link, '/./' or '/../' character. Zend_Filter_RealPath will return FALSE on failure, e.g. if the file does not exist. On BSD systems Zend_Filter_RealPath doesn't fail if only the last path component doesn't exist, while other systems will return FALSE.
Non existing pathsSometimes it is useful to get also paths when they don't exist, f.e. when you want to get the real path for a path which you want to create. You can then either give a FALSE at initiation, or use setExists() to set it.
StringToLowerThis filter converts any input to be lowercased. Supported options for Zend_Filter_StringToLowerThe following options are supported for Zend_Filter_StringToLower:
Basic usageThis is a basic example:
Different encoded stringsPer default it will only handle characters from the actual locale of your server. Characters from other charsets would be ignored. Still, it's possible to also lowercase them when the mbstring extension is available in your environment. Simply set the wished encoding when initiating the StringToLower filter. Or use the setEncoding() method to change the encoding afterwards.
StringToUpperThis filter converts any input to be uppercased. Supported options for Zend_Filter_StringToUpperThe following options are supported for Zend_Filter_StringToUpper:
Basic usageThis is a basic example for using the StringToUpper filter:
Different encoded stringsLike the StringToLower filter, this filter handles only characters from the actual locale of your server. Using different character sets works the same as with StringToLower.
StringTrimThis filter modifies a given string such that certain characters are removed from the beginning and end. Supported options for Zend_Filter_StringTrimThe following options are supported for Zend_Filter_StringTrim:
Basic usageA basic example of usage is below:
The above example returns 'This is (my) content:'. Notice that the whitespace characters have been removed. Default behaviour for Zend_Filter_StringTrim
The above example returns 'This is (my) content'. Notice that the whitespace characters and colon are removed. You can also provide an instance of Zend_Config or an array with a 'charlist' key. To set the desired character list after instantiation, use the setCharList() method. The getCharList() return the values set for charlist. StripNewLinesThis filter modifies a given string and removes all new line characters within that string. Supported options for Zend_Filter_StripNewLinesThere are no additional options for Zend_Filter_StripNewLines. Basic usageA basic example of usage is below:
The above example returns 'This is (my) content:'. Notice that all newline characters have been removed. StripTagsThis filter can strip XML and HTML tags from given content. Warning
Zend_Filter_StripTags is potentially unsecureBe warned that Zend_Filter_StripTags should only be used to strip all available tags. Using Zend_Filter_StripTags to make your site secure by stripping some unwanted tags will lead to unsecure and dangerous code. Zend_Filter_StripTags must not be used to prevent XSS attacks. This filter is no replacement for using Tidy or HtmlPurifier. Supported options for Zend_Filter_StripTagsThe following options are supported for Zend_Filter_StripTags:
Basic usageSee the following example for the default behaviour of this filter:
As result you will get the stripped content 'My content'. When the content contains broken or partitial tags then the complete following content will be erased. See the following example:
The above will return 'This contains' with the rest being stripped. Allowing defined tagsZend_Filter_StripTags allows stripping of all but defined tags. This can be used for example to strip all tags but links from a text.
The above example strips all tags but the link. By providing an array you can set multiple tags at once. Warning
Do not use this feature to get a probably secure content. This component does not replace the use of a proper configured html filter. Allowing defined attributesIt is also possible to strip all but allowed attributes from a tag.
The above example strips all tags but img. Additionally from the img tag all attributes but src will be stripped. By providing an array you can set multiple attributes at once.
|