PHP File Handling Function

8/10/2019 PHP File Handling Function

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File handling Function

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fopen()

The fopen() function is used to open files in PHP.

The first parameter of this function contains the

name of the file to be opened and the secondparameter specifies in which mode the file should

be opened.

If fopen is unable to open the file, it returns 0

(zero) otherwise it will return 1.

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Syntax and Example

var_name=fopen(file_name,file_open_mode)


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The file may be opened in one of the following modes

Modes Description

r Read only. Starts at the beginning of the file

r+ Read/Write. Starts at the beginning of the file

w Write only. Opens and clears the contents of

file; or creates a new file if it doesn't exist

w+ Read/Write. Opens and clears the contents of

file; or creates a new file if it doesn't exist

a Append. Opens and writes to the end of the

file or creates a new file if it doesn't exist

a+ Read/Append. Preserves file content by

writing to the end of the file

x Write only. Creates a new file. Returns

FALSE and an error if file already exists

x+ Read/Write. Creates a new file. Returns

FALSE and an error if file already exists

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fwrite()

The fwrite function allows data to be written to

any type of file and an open file.

The function will stop at the end of the file orwhen it reaches the specified length, whichever

comes first.

This function returns the number of bytes written

on success, or FALSE on failure.

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Syntax and Example

var_name =fwrite(file,string,length)


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fread()

The fread() reads from an open file.

The function will stop at the end of the file or

when it reaches the specified length, whichevercomes first.

fread() function returns the read string on success,or FALSE on failure.

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Syntax and Example

Syntax:


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$myFile = "testFile.txt";

$fh = fopen($myFile, 'r');

$theData = fread($fh, 5);

fclose($fh);

echo $theData;

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$myFile = "testFile.txt";

$fh = fopen($myFile, 'r');

$theData = fread($fh, filesize($myFile));

fclose($fh); echo $theData;

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fclose()

The fclose() function closes an open file.

fcose() function returns TRUE on success or

FALSE on failure.

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Syntax and Example

Syntax:

fclose(file)


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file_exists()

file_exists() function is used to check whether a

file or directory exists or not.

Return TRUE if the file or directory specifiedby file_name exists otherwise FALSE.

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Syntax and Example

Syntax:

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var_name=file_exists (file_name)


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is_readable

The is_readable() function is used to check whether

the specified file is readable or not.

TRUE if file_name exists and is readable, FALSE

otherwise.

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Syntax and Example

is_readable(file_name)

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is_writable()

The is_writable() function is used to check whether

the specified file is writeable.

TRUE if file_name exists and is writable.

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Syntax and Example

is_writable(file_name)

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fgets()

The fgets() function is used to get line from file

pointer of an open file.

The fgets() function stops returning on a new line, atthe specified length, or at EOF, whichever comes

first.

This function returns FALSE on failure.

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Syntax and Example

fgets(file_handler, byte_length)

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Name Descriptionfile_handler When a file is successfully opened by fopen() or

fsockopen() it returns a resource ID, which isreferred as file handler or file pointer. The fgets()function uses this ID to return a series of bytes

from an open filebyte_length Specifies the number of bytes to read. Default

length is 1024.


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fgetc()

The fgetc() function reads a single character from a

open file pointed by file handler..

A string containing a single character and FALSE onEOF.

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Syntax and Example

fgetc(file_handler)

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file()

The file() reads whole file into an array.

Each array element contains a line from the file, with

newline still attached.

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Syntax and Example

file(path,include_path,context)

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file_get_contents()

The file_get_contents() reads a whole file into astring.

file_get_contents (file_name, include_path_name, context,

star_position, max_length)

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Parameter Description

path Required. Specifies the file to read

include_path Optional. Set this parameter to '1' if you want to search for

the file in the include_path (in php.ini) as well

context Optional. Specifies the context of the file handle. Context is a

set of options that can modify the behavior of a stream. Canbe skipped by using NULL.

start Optional. Specifies where in the file to start reading. Thisparameter was added in PHP 5.1

max_length Optional. Specifies how many bytes to read. This parameter

was added in PHP 5.1

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Example

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file_put_contents()

The file_put_contents() function writes a stringto a file.

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file_put_contents(file,data,mode,context)


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Syntax and Example

Parameter Description

file Required. Specifies the file to write to. If the file does notexist, this function will create one

data Required. The data to write to the file. Can be a string, an array or adata stream

mode Optional. Specifies how to open/write to the file. Possible values:

FILE_USE_INCLUDE_PATHFILE_APPENDLOCK_EX

context Optional. Specifies the context of the file handle. Context is a set ofoptions that can modify the behavior of a stream.

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ftell()

The ftell() function is used to fetch the current

position of the file pointer of an open file.

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ftell(file_handler)


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PHP File Handling Function

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