Generate PHP codes with PHP
Throughout my programming years, I observed similar trends in code structures and I felt that being able to generate them automatically will greatly reduce development time.
Although there are many code generation software on the web, coding one for your own usage can be simpler and more convenient, especially when you had written custom functions that your generated codes will utilize.
In this post, I shall discuss my recent experience in creating a PHP code generator for my own usage.
A simple case study
Suppose that given a class name and a comma-delimited string of variable names:
1 2 3 4 | <?php $classname = 'Person' ; $variables = 'age, name' ; ?> |
We want to generate a POJO equivalence in PHP automatically, which resembles the following form:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 | <?php class Person { private $name ; private $age ; public function getName() { return $this ->name; } // end public function getName() public function setName( $name ) { $this ->name = $name ; } // end public function setName($name) public function getAge() { return $this ->age; } // end public function getAge() public function setAge( $age ) { $this ->age = $age ; } // end public function setAge($age) } // end class Person ?> |
Perform the necessary work
Capitalise the first character of the variable name
To capitalise the first character of the variable name to form the getXXX and setXXX methods, we can use the ucfirst
function.
1 2 3 4 | <?php // Form the method name of the getter method $getterMethodName = 'get' . ucfirst( 'age' ); ?> |
Get the end of line
The end of line is represented differently in different operating systems. Use the php constant PHP_EOL
instead of \r or \n to output the end of line in a cross platform manner.
1 2 3 4 | <?php // Variable contains the end of line character(s). $endOfLine = PHP_EOL; ?> |
Get the tab character
The tab character is represented with the \t literal. To output the tab character, enclose it with double quotes instead of single quotes. Using single quotes will display two characters \ and t instead of the tab character.
1 2 3 4 5 6 | <?php // Variable contains the tab character $tab = "\t" ; // Variable contains the \ and t characters $slashAndT = '\t' ; ?> |
Write the codes to file
To write the codes to file, we can use the fopen
and fwrite
functions.
1 2 3 4 5 6 7 8 9 | <?php // Save the generated file to a sibling folder of the running script $generatedFileUrl = dirname( $_SERVER [ 'SCRIPT_FILENAME' ]); $generatedFileUrl .= '/generated-codes/' . $className . '.inc.php' ; $fp = fopen ( $generatedFileUrl , 'w+' ); // Write the start script tag fwrite( $fp , '<?php' . PHP_EOL); ?> |
A sample (Plain Old PHP Object) POPO code generation script
The following is a sample script that I wrote for generating POPOs using the above-mentioned PHP features. Since this is a script to help developers, I did not include error handling to filter invalid class names or variable names. If you use it the right way, it can be helpful to you.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 | <?php $className = '' ; $variableNames = '' ; if (isset( $_POST [ 'text_class_name' ]) && isset( $_POST [ 'text_variable_names' ])) { $className = trim( $_POST [ 'text_class_name' ]); $variableNames = str_replace ( ' ' , '' , trim( $_POST [ 'text_variable_names' ])); $variableNamesArray = explode ( ',' , $variableNames ); // Save the generated file to a sibling folder of the running script $generatedFileUrl = dirname( $_SERVER [ 'SCRIPT_FILENAME' ]); $generatedFileUrl .= '/generated-codes/' . $className . '.inc.php' ; $fp = fopen ( $generatedFileUrl , 'w+' ); // Write the start script tag fwrite( $fp , '<?php' . PHP_EOL); fwrite( $fp , 'class ' . $className . ' {' . PHP_EOL . PHP_EOL); // Output the instance variables foreach ( $variableNamesArray as $variableName ) { fwrite( $fp , "\t" . 'private $' . $variableName . ';' . PHP_EOL); } fwrite( $fp , PHP_EOL); // Output the getter and setter methods foreach ( $variableNamesArray as $variableName ) { $ucVariableName = ucfirst( $variableName ); // getter fwrite( $fp , "\tpublic function get" . $ucVariableName . '() {' . PHP_EOL); fwrite( $fp , "\t\t" . 'return $this->' . $variableName . ';' . PHP_EOL ); fwrite( $fp , "\t} // end function get" . $ucVariableName . '()' . PHP_EOL . PHP_EOL); // setter fwrite( $fp , "\tpublic function set" . $ucVariableName . '($' . $variableName . ') {' . PHP_EOL); fwrite( $fp , "\t\t" . '$this->' . $variableName . ' = $' . $variableName . ';' . PHP_EOL); fwrite( $fp , "\t} // end function set" . $ucVariableName . '($' . $variableName . ')' . PHP_EOL . PHP_EOL); } // end foreach fwrite( $fp , '} // end class ' . $className . PHP_EOL); fwrite( $fp , '?>' ); } // end if ?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd" > <html xmlns= "http://www.w3.org/1999/xhtml" xml:lang= "en" lang= "en" > <head> <title>Create Plain Old PHP Object</title> </head> <body> <h1>Create Plain Old PHP Object</h1> <form method= "post" action= "<?php echo $_SERVER[" SCRIPT_NAME "];?>" > <fieldset> <label>Class name: </label> <input type= "text" name= "text_class_name" value= "<?php echo $className;?>" /> </fieldset> <fieldset> <label>Variable name(s), comma-delimited: </label> <input type= "text" name= "text_variable_names" value= "<?php echo $variableNames;?>" /> </fieldset> <input type= "submit" id= "submitButton" name= "submitButton" value= "Submit" /> </form> </body> </html> |