Fetching Options and Arguments - Zend_Console_Getopt
Fetching Options and Arguments
After you have declared the options that the Zend_Console_Getopt object should recognize, and supply arguments from the command-line or an array, you can query the object to find out which options were specified by a user in a given command-line invocation of your program. The class implements magic methods so you can query for options by name.
The parsing of the data is deferred until the first query you make against the Zend_Console_Getopt object to find out if an option was given, the object performs its parsing. This allows you to use several method calls to configure the options, arguments, help strings, and configuration options before parsing takes place.
Handling Getopt Exceptions
If the user gave any invalid options on the command-line, the parsing function throws a Zend_Console_Getopt_Exception. You should catch this exception in your application code. You can use the parse() method to force the object to parse the arguments. This is useful because you can invoke parse() in a try block. If it passes, you can be sure that the parsing won't throw an exception again. The exception thrown has a custom method getUsageMessage(), which returns as a string the formatted set of usage messages for all declared options.
Example #1 Catching Getopt Exceptions
Cases where parsing throws an exception include:
Option given is not recognized.
Option requires a parameter but none was given.
Option parameter is of the wrong type. E.g. a non-numeric string when an integer was required.
Fetching Options by Name
You can use the getOption() method to query the value of an option. If the option had a parameter, this method returns the value of the parameter. If the option had no parameter but the user did specify it on the command-line, the method returns TRUE. Otherwise the method returns NULL.
Example #2 Using getOption()
- $opts = new Zend_Console_Getopt('abp:');
- $b = $opts->getOption('b');
- $p_parameter = $opts->getOption('p');
Alternatively, you can use the magic __get() function to retrieve the value of an option as if it were a class member variable. The __isset() magic method is also implemented.
Example #3 Using __get() and __isset() Magic Methods
If your options are declared with aliases, you may use any of the aliases for an option in the methods above.
There are several methods to report the full set of options given by the user on the current command-line.
As a string: use the toString() method. The options are returned as a space-separated string of flag=value pairs. The value of an option that does not have a parameter is the literal string "TRUE".
As an array: use the toArray() method. The options are returned in a simple integer-indexed array of strings, the flag strings followed by parameter strings, if any.
As a string containing JSON data: use the toJson() method.
As a string containing XML data: use the toXml() method.
In all of the above dumping methods, the flag string is the first string in the corresponding list of aliases. For example, if the option aliases were declared like verbose|v, then the first string, verbose, is used as the canonical name of the option. The name of the option flag does not include any preceding dashes.
Fetching Non-option Arguments
After option arguments and their parameters have been parsed from the command-line, there may be additional arguments remaining. You can query these arguments using the getRemainingArgs() method. This method returns an array of the strings that were not part of any options.
Example #4 Using getRemainingArgs()
Zend_Console_Getopt supports the GNU convention that an argument consisting of a double-dash signifies the end of options. Any arguments following this signifier must be treated as non-option arguments. This is useful if you might have a non-option argument that begins with a dash. For example: "rm -- -filename-with-dash".