PHP Tutorial #16 String Methods (QuoteMeta, Rtrim , Sha1_file and Sha1 )

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Repository

https://github.com/php/php-src 

What Will I Learn?

I will learn the string methods this is the sixth part , we will take the " Quotemeta, Rtrim, Sha1_File and Sha1 " methods.   

• What's the quotemeta method and how to use it.
• How to delete from the right using Rtrim method.
• The concept of Sha1_file method and its uses.
• How to calculate the SHA-1 hash of a string using SHA1 method.

Requirements

• Server support PHP , Xampp or Wamp for example
• An IDE like Sublime text.
• Browser (Chrome for example) 

Difficulty

• Basic

Description

 1- QuoteMeta method 

The quotemeta function adds backslashes (a backslash \) in front of a few predefined characters in a string. 

It returns the string after inserting a backslash in front of all the following characters.

The predefined characters are

Point (.) 

backslash (\) 

plus (+) 

Multiplication sign (*)

interrogation point (?) 

Accolade [] 

sign of omission (^) 

dollar sign ($) 

parenthesis ()

It has the string as parameter and it returns a string. 

To use the quotemeta method you must pass the string as parameter

quotemeta($string)

I want to use an example with almost all the predefined characters to see the effect of the quotemeta method

echo "<h3>Quotemeta Method</h3>";

$string = "20 + 20 = 40$

20 * (20 - 10 ) = ?

20 - [20 - 10] = ?

20^20 = ?

 ";

echo quotemeta(nl2br($string));

I have used ' nl2br ' method to save the form of the string , I have explained this method in the previous tutorial , this is the result

2- Rtrim method 

The rtrim function returns the string after removing all end-of-string white characters. 

If it called without the second parameter rtrim will remove the following characters: 

-  "" (ASCII 32 (0x20))  an ordinary space. 

- "\ t" (ASCII 9 (0x09)), a tab. 

- "\ n" (ASCII 10 (0x0A))  a new line (line feed).

-  "\ r" (ASCII 13 (0x0D))  a carriage return.

- "\ 0" (ASCII 0 (0x00)) the character NUL. 

- "\ x0B" (ASCII 11 (0x0B)) a vertical tab. 

It has two parameters 

The first is the string to verify.

The second is the charlist .

To use the rtrim method you need to pass the string and the charlist as parameters

rtrim($string, charlist)

I have a string " I love Utopian " and I want to apply the rtrim method to this string to remove the work Utopian

$string2 = "I love Utopian";

echo rtrim($string2, "Utopian");

The method will remove from the right the characters passed as parameter and this is the result

3- Sha1_File Method

The sha1_file function calculates the SHA-1 hash of a file, calculate the sha1 of the file specified by the filename parameter using US Secure Hash Algorithm 1, then return that sha1. 

The sha1 is a hexadecimal number of 40 characters. it returns a string of characters on success, FALSE otherwise. 

It has two parameters  

The first is the file to calculate.

The second is a Boolean parameter , specifies the spell or binary result format:

TRUE - the binary format of 20 characters .

FALSE -By default, number of 40 characters .

To use the sha1_file you must pass the file name as parameter

sha1_file($file_name)

The file "Utopian.txt" contains the string " I love Utopian ! " I want to get the SHA-1 hash of the file using this method

$sha1_file = sha1_file("utopian.txt");

echo $sha1_file;

The method by default with the value false , it will return 40 characters  and this is the result

4- Sha1 Method

The sha1 function calculates the SHA-1 hash of a string, the function sha1 computes the sha1 of a strings using US Secure Hash Algorithm 1, it returns a string of characters on success, FALSE otherwise. 

It has two parameters  

The first is the string to calculate. 

The second is a the raw_output parameter , If the optional raw_output parameter is changed to TRUE, the sha1 is returned in raw binary form with a size of 20 characters, otherwise it is returned as a hexadecimal number with a size of 40 characters.  

To use the sha1 method you need to pass the string as parameter

sha1($string)

I want to get the SHA-1 hash of a string which is the same of the file " I love Utopian !" 

$string3 = "I love Utopian !";

$sha1 = sha1($string3);

echo $sha1;

Logically it will return the same value that the previous method returned with 40 characters, this is the result

Video Tutorial 

Curriculum

• PHP Tutorial #01 Indexed Arrays, Associative Arrays and Multidimensional Arrays
• PHP Tutorial #02 Array Methods (Sort, Rsort, Ksort, Krsort , Array_Reverse And Shuffle)
• PHP Tutorial #03 Array Methods ( Search Methods , Addition Methods and the Remove Methods)
• PHP Tutorial #04 Array Methods (Array_Sum, Array_Rand, Array_Column and Array_Unique)
• PHP Tutorial #05 Array Methods (Array_Chunk, Array_Combine, Array_Count_Values and Array_Product)
• PHP Tutorial #06  Array Methods (Array_Fill_Keys,Array_Fill, Array_Flip and Array_Filter)
• PHP Tutorial #07 Array Methods ( Array_Keys, Array_Map, Array_Merge and Array_Pad )
• PHP Tutorial #08 Array Methods ( Array_Replace, Array_Values, Array_Slice and Array_Intersect )
• PHP Tutorial #09 Array Methods (Array_Walk, Current, Next, Prev, End and Reset )
• PHP Tutorial #10 Array Methods (Array_Diff_Key, Array_Diff, Array_Intersect_Key and Array_Change_Key_Case )
• PHP Tutorial #11 String Methods ( Addslaches, Chr, Chop and Chunk_splite )
• PHP Tutorial #12 String Methods ( Bin2Hex, Count_Chars, Explode and Hex2Bin )
• PHP Tutorial #13 String Methods (Implode, Join, Lcfirst, Ltrim and Fprintf )
• PHP Tutorial #14 String Methods (Md5_File, Md5, Nl2br and Addcslaches )
• PHP Tutorial #15 String Methods (Number_Format, Ord, Parse_Str, Print and Printf )

Proof of Work Done 

https://github.com/alexendre-maxim/PHP-Tutorial/blob/master/string6.php