Python Append File | Write on Existing File | Examples

When you want an add content without deleting existing content, you have to use the Python Append File Handling scenario. Append methods in Python file handling use for add connote at the end of file content.

How to Python Append File?

How to open an existing file and write the content at the last, you have to use a python in build method (function) Open to get a file object. The file object has functions and attributes to content write an update in the file etc.

The syntax of Python Append File

Where file_obj is a variable to hold the file object. The mode argument is required as an ‘a’ because the default value of ‘r’ will be assumed if it is omitted. Where ‘a ‘value stands for append mode.

#Opening file
file_obj  = open("filename", "mode")
# write text into file 
file_obj.write("Append file")

Modes

Modes are important in Python file Handling, here are some types we are mentioning with detail.

• w write mode – if the file doesn’t exist create it and open it in write mode. The stream is positioned at the beginning of the file.
• r read mode – (Only read the file ) is the default in the open function. The stream is positioned at the beginning of the file.
• a append mode (if the file doesn’t exist create it and open it in append mode). The stream is positioned at the end of the file.

Examples of Python Append File:

Assume we have the empty “testFile.txt” file, located in the same folder as Python with content “Hello world“.

Now writing the file. ‘a’ – Append mode

f = open("testFile.txt", "a")
f.write(" Append file")

Output: in the text file

Do comment in below if any doubt and suggestion.

Note: This example (Project) is developed in PyCharm 2018.2 (Community Edition)
JRE: 1.8.0
JVM: OpenJDK 64-Bit Server VM by JetBrains s.r.o
macOS 10.13.6

Python 3.7

All Examples Python Append File and Write on Existing File are in Python 3, so it may change its different from python 2 or upgraded versions.