If you’re a Python programmer, you may have heard of the `writelines()` Method. But what exactly is it? The `writelines()` Method is a powerful tool that makes it easy to write a list of strings to a file. You can think of it as a shortcut for writing multiple lines to a file. It’s a great way to save time and effort when writing files.
The `writelines()` method in Python is a method that is used to write a list of strings to a file. It is a method of the File object in Python, which represents an open file. With `writelines()`, you don’t have to worry about formatting the lines correctly – it does it for you. All you have to do is provide a list of strings and the `writelines()` Method will handle the rest. Another great benefit of `writelines()` is that you can use it with any type of file – from plain text to audio and video files. So if you need a quick and easy way to write to a file, the `writelines()` Method is the perfect solution.
Syntax:
The `writelines()` method uses the following syntax:
1 | file_object.writelines(sequence) |
Here, sequence is the list of strings that is to be written to the file.
The writelines() method does not add any newline characters to the end of the strings in the list. If you want to add a newline character at the end of each string in the list, you can use the writelines() method in the following way:
1 | file_object.writelines([string + '\n' for string in sequence]) |
Example:
Let’s understand Python’s `writelines()` method with a few examples. Consider the following list of strings:
1 | lines = ['Apple', 'Banana', 'Mango', 'Orange', 'Pineapple'] |
- To write this list of strings to a file using the
`writelines()`method, you can do the following:1234567# Defining list of stringslines = ['Apple', 'Banana', 'Mango', 'Orange', 'Pineapple']# Open the file in write modewith open('myfile.txt', 'w') as f:# Write the list of strings to the filef.writelines(lines)This will create a file named “myfile.txt” in current directory and write all the strings strings in the list `lines` to the file, in a single line.
- You can also add a new line seprator `\n` write each string one per line. See the following example:1234567# Defining list of stringslines = ['Apple', 'Banana', 'Mango', 'Orange', 'Pineapple']# Open the file in write modewith open('myfile.txt', 'w') as f:# Write the list of strings to the filef.writelines([string + '\n' for string in lines])
This will create a file named myfile.txt and write the strings in the list lines to the file, one string per line, with a newline character at the end of each string.
- Note that the
`writelines()`method overwrites the contents of the file if it already exists. If you want to append the strings to the file, you can open the file in append mode using the ‘a’ flag instead of the ‘w’ flag.1234567# Defining list of stringslines = ['Apple', 'Banana', 'Mango', 'Orange', 'Pineapple']# Open the file in append modewith open('myfile.txt', 'a') as f:# Write the list of strings to the filef.writelines([string + '\n' for string in lines])This will append the strings in the list lines to the end of the file myfile.txt.
The `writelines()` method is generally faster than writing to a file using a loop and the write() method, as it writes all the strings in the list to the file in a single call. However, it is important to note that the `writelines()` method does not add any newline characters to the end of the strings in the list, so you may need to add them manually if you want to write each string to a new line in the file.
