We must first open a file before we can read or write to it. Use Python’s built-in Here’s an example of how to use Python’s We specified two parameters. The first is the file name<\/strong>, and the second is the mode<\/strong>, which determines the mode in which we want to open the file.<\/p>\n\n\n\n There are several modes to open files, and the most commonly used ones are listed below.<\/p>\n\n\n\n To specify in which mode a file should be handled, we can use<\/strong><\/p>\n\n\n\n Hence, the primary task is to open a file on which you must operate and specify the mode specific to the work you wish to perform on the file.<\/p>\n\n\n\n We can open the file reading mode after specifying the file name to the To perform this operation, we have a file called We successfully read the content inside the file by iterating them using the Python We can use When we’re done working with files, we need to close them so that the resources associated with them can be released. After working with a file, it is best practice to close it.<\/p>\n\n\n\n We can use The code returned True<\/strong> which means the file was closed successfully.<\/p>\n\n\n\n Python’s Here, As we saw in the upper section, if we want to write data into the file then we need to use the In the following code, we’ll create a new file and then write some content inside it.<\/p>\n\n\n\n The file name What do you think will happen if we try to add more content inside the The previous content will be erased and the new content will be written.<\/p>\n\n\n\n We can append data to files by opening them in The Now that we have some content stored in two different lines in our file, it’s a good time to demonstrate the The Binary( We’ll get data as shown in the image below.<\/p>\n\n\n\n The following code will show how we can write binary data into the file.<\/p>\n\n\n\n We overrode the image file’s previous content and added new content. Now, if we read the image’s bytes, we’ll get the output shown below.<\/p>\n\n\n\n The image file is now corrupted and we won’t be able to open this image.<\/p>\n\n\n\n When we encounter errors or exceptions while performing a specific operation on a file, the program exits without closing the file. As a result, we must take precautions to address this issue.<\/p>\n\n\n\n We can use a The above code will return an error stating that the read operation is not supported, but instead of terminating immediately, the program will run the block of code written within the Here’s a simple Python program that prompts the user to select which operations they want to perform after they enter their name. When a user performs an adoption operation, the name is saved in the file along with the current timestamp. The user can view the information stored in the file by performing the information operation.<\/p>\n\n\n\n Go ahead and run it in your code editor and also try to make a better version of it.<\/p>\n\n\n\n With code examples, we learned the fundamental operations of creating, reading, writing, and closing files in this article. To perform these operations, the file must first be opened, and then the mode specific to the operation we want to perform on the file must be specified.<\/p>\n\n\n\n If no mode is specified, read<\/strong> and text<\/strong> mode is used to open a file, and we can also write and read binary data from the file.<\/p>\n\n\n\n We’ve also written a Python program in which a user can adopt a pet for themselves, and the data is saved in a file.<\/p>\n\n\n\n \ud83c\udfc6Other articles you might be interested in if you liked this one<\/strong><\/p>\n\n\n\n \u2705How to open and read multiple files simultaneously in Python<\/a>.<\/p>\n\n\n\n \u2705Reading and writing zip files without extracting them in Python<\/a>.<\/p>\n\n\n\n \u2705Perform high-level file operations on the file using the shutil module in Python<\/a>.<\/p>\n\n\n\n \u2705Take multiple inputs from the user in a single line in Python<\/a>.<\/p>\n\n\n\n \u2705enumerate() function in Python<\/a>.<\/p>\n\n\n\nopen()<\/code> function to perform this operation on the file.<\/p>\n\n\n\nopen()<\/code> function.<\/p>\n\n\n\nfile_obj = open('file.txt', mode='r')<\/code><\/p>\n\n\n\nr<\/code> – Read<\/strong>. The file opens in read mode. Shows an error if the file doesn’t exist.<\/p>\n\n\n\nw<\/code> – Write<\/strong>. The file opens in write mode. Creates a file if the file doesn’t exist.<\/p>\n\n\n\na<\/code> – Append<\/strong>. The file opens in append mode. Writes data into an existing file.<\/p>\n\n\n\nx<\/code> – Create<\/strong>. Creates a file. If the specified file exists, returns an error.<\/p>\n\n\n\nt<\/code> – Text<\/strong>. The file opens in text mode which means the file will store text data. It is a default mode.<\/p>\n\n\n\nb<\/code> – Binary<\/strong>. The file opens in the binary mode which means the file will store binary data.<\/p>\n\n\n\n<\/a>Reading a file<\/h2>\n\n\n\n
open()<\/code> function. This is the default value; if the mode parameter is not specified, the file will open in the default read<\/strong> and text<\/strong> mode.<\/p>\n\n\n\ntext_file.txt<\/code> which has some content inside it.<\/p>\n\n\n\n# Using open() function\nfile = open('text_file.txt', 'r')\n# Printing the content inside the file\nfor content in file:\n print(content)\n\n----------\nHey, there Geeks. Welcome to GeekPython.<\/pre><\/div>\n\n\n\nfor<\/code> loop.<\/p>\n\n\n\n<\/a>Using read()<\/h3>\n\n\n\n
file.read()<\/code> to read the characters from the file. Here’s a code that will read the content from the file.<\/p>\n\n\n\n# Using open() function\nfile = open('text_file.txt', 'r')\n# Reading file using read()\nprint(file.read())\n\n----------\nHey, there Geeks. Welcome to GeekPython.<\/pre><\/div>\n\n\n\n<\/a>Closing the file<\/h3>\n\n\n\n
file.close()<\/code> to close the current working file.<\/p>\n\n\n\n# Using open() function\nfile = open('text_file.txt', 'r')\n# Reading file using read()\nprint(file.read())\n\n# Closing the file\nfile.close()\n# Checking if the file is closed or not\nprint(file.closed)\n\n----------\nHey, there Geeks. Welcome to GeekPython.\nTrue<\/pre><\/div>\n\n\n\n<\/a>Using with keyword<\/h3>\n\n\n\n
open()<\/code> is a context manager, so we can use with<\/code> keyword with it to open and read the file’s content.<\/p>\n\n\n\n# Using with keyword\nwith open('text_file.txt', 'r') as file:\n # Printing the content\n print(file.read())<\/pre><\/div>\n\n\n\nopen()<\/code> will open the file and returns the file object and then the as<\/code> keyword will bind the returned value to the file<\/code>. We can now use file<\/code> to print the content. Then the file will be automatically closed.<\/p>\n\n\n\n<\/a>Writing into file<\/h2>\n\n\n\n
'w'<\/code> mode. But before writing data into the file, remember that<\/p>\n\n\n\n\n
# Creating and writing in a file\nwith open('test.txt', 'w') as file:\n # Writing data inside the file\n file.write('You guys are awesome, Thanks for reading.')\n print('Data written successfully.')\n\n # Closing the file\n file.close()\n\n----------\nData written successfully.<\/pre><\/div>\n\n\n\ntest.txt<\/code> will be created and the content will be written inside it.<\/p>\n\n\n\n![\"File](\"https:\/\/geekpython.in\/wp-content\/uploads\/2023\/08\/1-9.png\")
<\/figure>\n\n\n\ntest.txt<\/code> file and run the above code?<\/p>\n\n\n\n# Writing in a file\nwith open('test.txt', 'w') as file:\n # Writing data inside the file\n file.write('If you love this, Bookmark it and share this.')\n print('Data written successfully.')\n\n # Closing the file\n file.close()\n\n----------\nData written successfully.<\/pre><\/div>\n\n\n\n![\"Content](\"https:\/\/geekpython.in\/wp-content\/uploads\/2023\/08\/2-10.png\")
<\/figure>\n\n\n\n<\/a>Appending data to the file<\/h3>\n\n\n\n
'a'<\/code> mode. This will not overwrite our existing content but rather add new data to the file.<\/p>\n\n\n\n# Adding new data to the file\nwith open('test.txt', 'a') as file:\n # Writing new data\n file.write('\\nPlease check other articles on GeekPython.')\n print('Data written successfully.')\n\n # Closing the file\n file.close()\n\n----------\nData written successfully.<\/pre><\/div>\n\n\n\ntest.txt<\/code> file will be opened in append mode, and the content will be appended to it without overwriting any existing data.<\/p>\n\n\n\n![\"Data](\"https:\/\/geekpython.in\/wp-content\/uploads\/2023\/08\/3-7.png\")
<\/figure>\n\n\n\n<\/a>Using readlines()<\/h3>\n\n\n\n
readlines()<\/code> function.<\/p>\n\n\n\nwith open('test.txt', 'r') as file:\n # Reading first line\n print(file.readline())\n # Reading second line\n print(file.readline())\n\n# Closing the file\nfile.close()\n\n----------\nIf you love this, Bookmark it and share this.\n\nPlease check other articles on GeekPython.<\/pre><\/div>\n\n\n\nreadlines()<\/code> function allows us to read the content of the file line by line. Our test.txt<\/code> file contains two lines so we used the readlines()<\/code> function twice.<\/p>\n\n\n\n<\/a>Reading & writing binary data<\/h2>\n\n\n\n
'b'<\/code>) mode is available for reading and writing binary data. We must specify 'rb'<\/code> to read the binary content from the file, and similarly, 'wb'<\/code> to write binary data into the file.<\/p>\n\n\n\n# Opening an image file in read binary mode\nwith open('writing.png', 'rb') as f:\n # Reading the bytes of the image\n print(f.read())\n f.close()<\/pre><\/div>\n\n\n\n![\"Bytes](\"https:\/\/geekpython.in\/wp-content\/uploads\/2023\/08\/4-7.png\")
<\/figure>\n\n\n\n# Opening image in write binary mode\nwith open('writing.png', 'wb') as binary_file:\n # Overriding the bytes of the image\n binary_file.write(b'Hello there')\n\n # Closing the file\n binary_file.close()<\/pre><\/div>\n\n\n\n![\"Image](\"https:\/\/geekpython.in\/wp-content\/uploads\/2023\/08\/5-6.png\")
<\/figure>\n\n\n\n<\/a>Exception handling – try… finally<\/h2>\n\n\n\n
try-finally<\/code> block to handle the exception. The following code shows how to use it.<\/p>\n\n\n\ntry:\n file = open('test.txt', 'w')\n # Writing content\n write_data = file.write(\"Hey, how it's going.\")\n # Trying to read the content\n read_data = file.read()\n print(read_data)\nfinally:\n # Closing the file\n file.close()\n # Printing if file is closed\n print(file.closed)<\/pre><\/div>\n\n\n\nfinally<\/code> block, resulting in the file being closed.<\/p>\n\n\n\nTraceback (most recent call last):\n ....\n read_data = file.read()\nio.UnsupportedOperation: not readable\nTrue<\/pre><\/div>\n\n\n\n
<\/a>Bonus – Pet Adoption project<\/h2>\n\n\n\n
'''\nA Python program to adopt a pet and appending the details in a file.\nThe entry can also be viewed by reading the file\n'''\n\nimport datetime\n\n\n# Defining main function\ndef get_pet(pet):\n # If user input 1 then this condition executes\n if pet == 1:\n adopt = int(input(\"Press 1 for Pet Dog 2 for Pet Cat: \\n\"))\n\n if adopt == 1:\n with open(\"Pet-Dog.txt\", \"a\") as f:\n f.write(str(datetime.datetime.now()) + \": \" + f\"{name_inp} just adopted a Dog. \\n\")\n print(\"Successfully Entered.\")\n\n elif adopt == 2:\n with open(\"Pet-Cat.txt\", \"a\") as f:\n f.write(str(datetime.datetime.now()) + \": \" + f\"{name_inp} just adopted a Cat. \\n\")\n print(\"Successfully Entered.\")\n\n else:\n print(\"We have only CATS and DOGS.\")\n\n # If usr input 2 then this condition executes\n elif pet == 2:\n info = int(input(\"Enter 1 for Pet Dog Details 2 for Pet Cat Details: \\n\"))\n if info == 1:\n with open(\"Pet-Dog.txt\") as f:\n for content in f:\n print(content, end='')\n\n elif info == 2:\n with open(\"Pet-Cat.txt\") as f:\n for content in f:\n print(content, end='')\n\n else:\n print(\"Enter Valid Option!!\")\n\n else:\n print(\"Choose 1 for adoption and 2 for Information...\")\n\n\nif __name__ == '__main__':\n print(\"------------ Welcome to Pet Adoption Center -----------\")\n\n # Username Input\n name_inp = input(\"Enter your name: \\n\")\n\n # Taking Input from users\n user_input = int(input(\"Press 1 for Adoption 2 for Information: \\n\"))\n\n # Conditions according to user input\n if user_input == 1:\n get_pet(user_input)\n else:\n get_pet(user_input)<\/pre><\/div>\n\n\n\n<\/a>Conclusion<\/h2>\n\n\n\n
\n\n\n\n