How to Parse a Tab-Delimited Text File Into an Array in PHP

Use PHP to parse tab-delimited files to arrays.

PHP is an open source programming language that can be used to create dynamic web pages. PHP code placed in HTML executes on the server and PHP has a variety of built-in types, such as strings, objects and arrays. PHP offers a variety of functions for accomplishing many common tasks, such as opening and reading files, working with strings and writing values into arrays. PHP also has a variety of variable-handling functions that provide shortcuts for printing variables, retrieving variable data types and working with cookies.

Things You'll Need

• Text editor
• Web server with PHP 4 or 5 installed and configured
• Web browser

Instructions

1. Open a text editor and type some tab-delimited values in a new file. Enter the values by inserting a "tab" character in between each value. Save the file on the web server with the name "tabbedTextFile.txt", noting the file's location. The "(tab)" text is shown to illustrate the tabs separating each value. Save and close tabbedTextFile.txt.

   value1(tab)value2(tab)value3(tab)value4(tab)value5

2. Return to the text editor and type a "<?php" and a "?>" PHP delimiter. These delimiters tell the server to interpret any code placed between them as PHP code. Open tabbedTextFile.txt for reading using the PHP "fopen()" function and write the returned value to a variable named "$openFile". Save the file as "parseToArray.php".

   <?php

   $openFile = fopen("tabbedTextFile.txt", "r");

   ?>

3. Continue editing parseToArray.php. Use the PHP "fread()" function to read the contents of tabbedTextFile.txt to a variable named "$fileContents". Use the PHP "filesize()" function to indicate that the entire file should be read.

   <?php

   $openFile = fopen("tabbedTextFile.txt", "r");

   $fileContents = fread($openFile, filesize("tabbedTextFile.txt"));

   ?>

4. Continue editing parseToArray.php and enter the PHP "fclose()" function. This function closes tabbedTextFile.txt.

   <?php

   $openFile = fopen("tabbedTextFile.txt", "r");

   $fileContents = fread($openFile, filesize("tabbedTextFile.txt"));

   fclose($openFile);

   ?>

5. Continue editing parseToArray.php. Identify the delimiter (tab) that should be used when parsing tabbedTextFile.txt. Store the delimiter to a variable named "$delimiter".

   <?php

   $openFile = fopen("tabbedTextFile.txt", "r");

   $fileContents = fread($openFile, filesize("tabbedTextFile.txt"));

   fclose($openFile);

   $delimiter = " ";

   ?>

6. Continue editing parseToArray.php. Use the PHP "explode()" function to extract the values in tabbedTextFile.txt, specifying that delimiter stored in $fileContents (tab). Write the exploded values to a variable named "$myArray". The "explode()" function returns an array of values.

   <?php

   $openFile = fopen("tabbedTextFile.txt", "r");

   $fileContents = fread($openFile, filesize("tabbedTextFile.txt"));

   fclose($openFile);

   $delimiter = " ";

   $myArray = explode($delimiter, $fileContents);

   ?>

7. Continue editing parseToArray.php. Print the values of $myArray array using the "print_r" command. The "print_r" command prints readable information about a variable. Save and close parseToArray.php.

   <?php

   $openFile = fopen("tabbedTextFile.txt", "r");

   $fileContents = fread($openFile, filesize("tabbedTextFile.txt"));

   fclose($openFile);

   $delimiter = " ";

   $myArray = explode($delimiter, $fileContents);

   print_r($myArray);

   ?>

8. Open a web browser and access parseToArray.php on the web server. Verify that the array values are printed on the web page.

Tips & Warnings

• The "print_r" command is not the only way to display an array's values. Looping through the array can retrieve these values and the array can be manipulated with PHP's built-in array functions.

• PHP requires proper configuration on the web server. See the Resources section for information on PHP installation and configuration.

• The behavior of variable-handling functions is affected by the settings in php.ini.

References

• The UK Web Design Company: Reading a Delimited File Using PHP
• PHP Manual: print_r
• PHP Manual: Filesystem Functions

Resources

• PHP Manual: Arrays