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Category: php functions

How to Use md5_file()php function

md5 is a mathematical algorithm that is commonly called the md5 digest. The md5 procedure takes alphanumeric input and performs what is known as a hash returning a 128 bit unique sequence of 32 hexadecimal digits. This technique is used for security reasons. You will find cases of it used on the Internet when there is a file that is offered for download, included with the file will be a "hash" value. The idea is to download the file and then perform an md5 hash on it. If the number that is returned matches the hash value that was offered with the file -- the user can be reasonably sure that the file was not corrupted. The hash value becomes a type of fingerprint because the value of a file can only be produced by an identical copy the original.

This technique is also used for storing and retrieving passwords, especially on internet websites. The most common way to store a person's credentials in an online database is with the md5 hash. When the person submits their password it gets "hashed". The 32 character hash is what is stored in the database. This way if the database was compromised and the passwords retrieved, the attacker would have nothing more than a bunch of 32 character strings that are not to look at.

There was a time when the md5 was considered uncrackable. That has changed over the past decade. As computers grew more powerful and smaller, mathematicians were able to start working with larger sets of numbers and variables at faster speeds - in the end discovering that the md5 hash can be broken. It was discovered that with the rightnumber crunching hardware the algorithm will start returning duplicates. This fact officially makes the md5 unsuitable for serious security use.

Md5 is still popular and in widespread use for modern software, because it spent close to 2 two decades un-cracked. Until recently, within a few short years, software vendors felt sure that md5 was a one way encryption that they could rely on, so they integrated into many of the password routines found in popular software such as Wordpress and OsDate.

Thus far we have discussed the md5 algorithm. Now let us take a look at how to use it in our php scripts.

  1. Create a folder called md5.
  2. Create a file called test_file.txt and save it in the md5 folder.
  3. Create another file called md5_file.php and save it in the md5 folder.
  4. Write the word "Testing" into the test_file.txt
  5. Copy and paste the script below into the md5_file.php file and save it

See Also:


Author: D.Shaun Morgan

ob start

How to Use ob_start() - PHP8/12/2014bool ob_start ([ callback $output_callback [, int $chunk_size [, bool $erase ]]] )ob_start holds everything except for headers on a webpage - i.e the whole script, html, etcetera in an internal memory

str ireplace

mixed str_ireplace ( mixed $search , mixed $replace , mixed $subject [, int &$count ] ) Str_ireplace() searches and replaces programmer defined strings in a string, variable or variable array. Str_ireplace() is useful for reforma


rtrimRemoves whitespace from the right side of a stringSeetrim()ltrim()


chop() PHP Functionchop() is identical to the rtrim function string rtrim(string $str[, string $charlist ])Strips characters including hex characters and hidden chars from the right most position in a string.Default strips

array rand

array_rand(array $input [, int $num_req= 1 ])ReturnsRandom keyArgumentsArgument 1 is an array. Arguments 2 is an integer that determines how many keys will be returnedThe script below uses the random function to shuffle around the array indexes in con

file get contents

file_get_contents PHP Functionfile_get_contents() streams in the content of a files that is passed to it as an argument.<?php$x = file_get_contents('testFile.txt);echo $x;

strip tags

StripTags() php function Striptags() is a php function that literally strips HTML tags out of files that are streamed in to php with a function like file_get_contents()

var dump

var_dump()var_dump() is very useful when you want to know what is inside of a php variable at certain spot in your php script.Arguments Passedvar_dump($variableToInspect)


The die function Die('') is a very useful php function. You can place "die anywhere in a script that want that script to terminate. It also provides a bit of feedback to help the programmer when he/she needs to figure out where the script was last executing.


string addcslashes(string $str , string $charlist)How to use addslashes<?php$SlashedString = 'Myexample';$char_list = 'ea';$StrippedString = add


string ucwords(string $mystring)Takes This function takes a string.Returns Converts every first letter of every word to an upper case letter.


trim() - phpTrims off white spaces from the beginning and ending of strings.$text = ' test ';$text =trim($text);echo $text;//gives 'test' with the white spaces gone

substr count

How to use substr_count() int substr_count ( string $haystack , string $needle [, int $offset= 0 [, int $length ]] )substr_count ( string $haystack , string $needle [, int $offset= 0 [, int $length ]] )


strtoupper() - php$str = 'this string is all upper case';echo strtoupper($str); ResultTHIS STRING IS ALL UPPER CASE


strlen($string)Gives the length of string supplied arguments


How to use stripslashes<?php$exampleString = 'My\ex\ampl\e';$charlist = 'ea';$StrippedString = stripslashes( $exampleString);echo $StrippedString;

str word count

str_word_count() phpCounts the numbers of words found in a string.Result

parse str

How to use parse_str()parse_str(string $str [,array &$arr ]) <?php$string = 'firstVar=first&secondVar=second&thirdVar=third';parse_str($string);echo $


nl2br() - How to convert newline characters to line breaks HTMLTo preserve the layout of characters type into a text-box and format it to display in an HTML documentnl2br() is a handy function.Simply pass into the


md5() md5 is a mathematical algorithm that is commonly called the md5 digest. The md5 procedure takes alphanumeric input and performs what is known as a hash returning a 128 bit unique sequence of 32 hexadecimal digits. This technique is sometimes used for security reaso

md5 file

How to Use md5_file()php functionmd5 is a mathematical algorithm that is commonly called the md5 digest. The md5 procedure takes alphanumeric input and performs what is known as a hash returning a 128 bit unique sequence of 32 hexadecimal digits. This technique is used f


ltrim ltrim() php functionltrim removes the leftmost entity from a string in PHP." " (ASCII 32 (0x20) - space. "\t" (ASCII 9 (0x09)) - tab. "" (ASCII 10 (0x0A) - (line feed)."\r" (ASCII 13 (0x0D))carriage return."\0" (ASCII 0 (0x00)) - Null Byte."\x0B" (ASCI


how to use implode() php functionThe implode() php function is exactly the opposite of explode(). It takes an array of strings and combines them together returning one single string.$content[0]


explode(); The explode(); php function is one that is used a lot. For example, you might want to read website content into a php script and then parse and manipulate that content. the explode php function basically chops the content up into smaller pieces


echoEcho is used in php scripts to output html characters to the screen. echo is one of the most used functions in the php language.


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