Opening a File
It is done using the open() function. No module is required to be imported for this function.
Syntax:
File_object = open(r"File_Name", "Access_Mode")
The file should exist in the same directory as the python program file else, full address of the file should be written on place of filename. Note: The r is placed before filename to prevent the characters in filename string to be treated as special character. For example, if there is \temp in the file address, then \t is treated as the tab character and error is raised of invalid address. The r makes the string raw, that is, it tells that the string is without any special characters. The r can be ignored if the file is in same directory and address is not being placed.
Python3
# Open function to open the file "MyFile1.txt" # (same directory) in read mode and file1 = open("MyFile.txt", "r") # store its reference in the variable file1 # and "MyFile2.txt" in D:\Text in file2 file2 = open(r"D:\Text\MyFile2.txt", "r+") |
Here, file1 is created as object for MyFile1 and file2 as object for MyFile2.
How to read from a file in Python
Python provides inbuilt functions for creating, writing and reading files. There are two types of files that can be handled in python, normal text files and binary files (written in binary language, 0s and 1s).
- Text files: In this type of file, Each line of text is terminated with a special character called EOL (End of Line), which is the new line character (‘\n’) in python by default.
- Binary files: In this type of file, there is no terminator for a line and the data is stored after converting it into machine-understandable binary language.
Note: To know more about file handling click here.
Access mode
Access modes govern the type of operations possible in the opened file. It refers to how the file will be used once it’s opened. These modes also define the location of the File Handle in the file. File handle is like a cursor, which defines from where the data has to be read or written in the file. Different access modes for reading a file are –
- Read Only (‘r’) : Open text file for reading. The handle is positioned at the beginning of the file. If the file does not exists, raises I/O error. This is also the default mode in which file is opened.
- Read and Write (‘r+’) : Open the file for reading and writing. The handle is positioned at the beginning of the file. Raises I/O error if the file does not exists.
- Append and Read (‘a+’) : Open the file for reading and writing. The file is created if it does not exist. The handle is positioned at the end of the file. The data being written will be inserted at the end, after the existing data.
Note: To know more about access mode click here.