Read Txt File Data From All the Folders Python

In Python, there are a few means you tin read a text file.

In this commodity, I will go over the open() part, the read(), readline(), readlines(), shut() methods, and the with keyword.

What is the open() function in Python?

If you lot want to read a text file in Python, y'all start take to open information technology.

This is the basic syntax for Python's open() function:

                open up("name of file you want opened", "optional manner")              

File names and correct paths

If the text file and your current file are in the same directory ("folder"), then you lot can simply reference the file name in the open() part.

                open("demo.txt")              

Here is an case of both files being in the same directory:

If your text file is in a different directory, and so you volition need to reference the correct path name for the text file.

In this example, the random-text file is within a different binder and then master.py:

In order to access that file in the main.py, you have to include the folder name with the name of the file.

                open("text-files/random-text.txt")              

If you don't take the correct path for the file, then y'all will become an error message similar this:

                open("random-text.txt")              

It is really important to keep track of which directory you are in and so y'all can reference the correct path proper noun.

Optional Style parameter in open up()

In that location are unlike modes when you are working with files. The default fashion is the read fashion.

The letter of the alphabet r stands for read style.

                open up("demo.txt", mode="r")              

You can also omit fashion= and just write "r".

                open("demo.txt", "r")              

In that location are other types of modes such as "west" for writing or "a" for appending.  I am not going to get into detail for the other modes because we are just going to focus on reading files.

For a complete list of the other modes, please read through the documentation.

Additional parameters for the open up() function in Python

The open() office can take in these optional parameters.

• buffering
• encoding
• errors
• newline
• closefd
• opener

To acquire more about these optional parameters, delight read through the documentation.

What is the readable() method in Python?

If you want to check if a file can be read, then you lot tin use the readable() method. This will return a True or False.

This example would return True considering we are in the read mode:

                file = open("demo.txt") impress(file.readable())              

If I inverse this example, to "w" (write) fashion, then the readable() method would return False:

                file = open up("demo.txt", "westward") impress(file.readable())              

What is the read() method in Python?

The read() method is going to read all of the content of the file as one string. This is a skilful method to employ if you don't have a lot of content in the text file.

In this example, I am using the read() method to print out a list of names from the demo.txt file:

                file = open("demo.txt") impress(file.read())              

This method can take in an optional parameter chosen size. Instead of reading the whole file, only a portion of it volition be read.

If nosotros modify the earlier example, we can print out merely the first word past adding the number 4 as an argument for read().

                file = open up("demo.txt") print(file.read(four))              

If the size argument is omitted, or if the number is negative, then the whole file will be read.

What is the shut() method in Python?

One time you are done reading a file, it is important that you close it. If you forget to close your file, so that tin cause issues.

This is an example of how to close the demo.txt file:

                file = open up("demo.txt") impress(file.read()) file.shut()              

How to use the with keyword to close files in Python

One fashion to ensure that your file is airtight is to use the with keyword. This is considered good practice, because the file will close automatically instead of you having to manually close it.

Here is how to rewrite our example using the with keyword:

                with open up("demo.txt") equally file:     print(file.read())              

What is the readline() method in Python?

This method is going to read one line from the file and return that.

In this case, we have a text file with these two sentences:

                This is the first line This is the 2nd line              

If nosotros utilize the readline() method, information technology will only print the start sentence of the file.

                with open up("demo.txt") every bit file:     print(file.readline())              

This method also takes in the optional size parameter. Nosotros can change the case to add the number 7 to only read and print out This is:

                with open("demo.txt") as file:     impress(file.readline(vii))              

What is the readlines() method in Python?

This method will read and return a list of all of the lines in the file.

In this example, we are going to print out our grocery items as a list using the readlines() method.

                with open("demo.txt") as file:     print(file.readlines())              

How to use a for loop to read lines from a file in Python

An alternative to these dissimilar read methods would exist to employ a for loop.

In this example, we can print out all of the items in the demo.txt file by looping over the object.

                with open("demo.txt") as file:     for item in file:         impress(item)              

Conclusion

If you want to read a text file in Python, you showtime accept to open up it.

                open("name of file you lot want opened", "optional mode")                              

If the text file and your current file are in the aforementioned directory ("folder"), then yous tin can merely reference the file name in the open() function.

If your text file is in a different directory, and then you will need to reference the right path proper name for the text file.

The open() function takes in the optional mode parameter. The default mode is the read manner.

                open("demo.txt", "r")              

If you desire to check if a file can be read, so you tin can use the readable() method. This will render a True or Imitation.

                file.readable()              

The read() method is going to read all of the content of the file every bit one string.

                file.read()              

Once you are done reading a file, it is important that you close it. If you forget to close your file, and then that tin can crusade issues.

                file.shut()              

One way to ensure that your file is airtight is to use the with keyword.

                with open("demo.txt") as file:     impress(file.read())              

The readline() method is going to read one line from the file and return that.

                file.readline()              

The readlines() method will read and return a list of all of the lines in the file.

                file.readlines()              

An alternative to these different read methods would be to employ a for loop.

                with open("demo.txt") as file:     for detail in file:         impress(detail)              

I hope you enjoyed this commodity and all-time of luck on your Python journey.

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