Python Basic file operations (file input and output)

File object methods commonly used in document input and output:

Open : Returns a new file object, calling the method on the object to do anything to the file

ReadLine : read a line you give oh if you include the end of the line break

Write : writing data to a file

Close : close File object;

Example: Read the Work.txt file in E-drive

f = open (' work.txt ') line =f.readline () print (line) f.close ()

If you set a parameter to ReadLine n then read n characters not set then read only one line including the end of the line break

Output Result:

What is Words (A tribute to Chris Medina)-Ameritz-tribute

We read all the data in the file through a while loop:

f = open (' e:/work.txt '), line = F.readline (), while Line:print (line); line = F.readline (); F.close ();

The program loops through all the rows in the file work.txt if the program is on a dataset like this, such as an input line, number, string, loop We are often called iterations ; Python provides a dedicated statement for iterating over all the content items of the output file:

For on open (' E:/work.txt '): print (line);

To perform a write operation on a file:

f = open (' E:/work.txt ', ' W '); #w: The file open Mode W indicates an executable write operation if F:f.write (' What is Words '); f.close;

Output Result:

What is Words

Add:

Methods in file operation:

read: Reads n characters from a file acts all characters when given a parameter

seek : move pointer first parameter offset second parameter: from where to start 0 1 current position 2 end

writelines : writing a sequence of strings

Mode of opening file in file operation:

r: Read mode open

W: Write to overwrite content in original file

A: Write to open in the original content to perform an append write operation

In PHP , file manipulation is similar to Python:

File manipulation functions:

fopen: Open File Common open way:

R: Read-only mode open

r+: Read and write mode open

W: pointer start position, write open file does not exist then create

w+: Start position of pointer, read and write open file does not exist then create

A: Pointer trailing position write open file does not exist then create

A +: pointer trailing position read-write mode open file does not exist then create

fread: Reading content

Fwrite: Write Content

Fgets: Get a row or n characters

Fgetc Get a Byte

Fseek: Move pointer 0 to initial position

ReadFile: Output a file

When you use Fread ($file, filesize) fgets fgetc and other methods to output content, use the Fseek method to move the pointer to the initial position if it is empty

For example:

$filename = ' E:/work.txt '; $file = fopen (filename, ' w+ '); $content = ' This was my house '; Fwrite ($file, $content); Echo ReadFile (filename); Output file Contents fseek ($file, 0); $str = Fread ($file, FileSize ($filename)); Only Fread example Var_dump ($STR); fclose ($file);

Summarize:

1,ptyhon file operation method;

2, the method for iterating the output in Python:

For line in Filedir:

3, PHP file output operation comparison;

This article is from the "Hong Dachun Technical column" blog, please be sure to keep this source http://hongdachun.blog.51cto.com/9586598/1759601

Python Basic file operations (file input and output)