Python File Open
Open a File on the Server
Assume we have the following file, located in the same folder as Python:
demofile.txt
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Hello! Welcome to demofile.txtThis file is for testing purposes.Good Luck!
To open the file, use the built-in open() function.
The open() function returns a file object, which has a read() method for reading the content of the file:
If the file is located in a different location, you will have to specify the file path, like this:
Example
Open a file on a different location:
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f = open("D:\\myfiles\welcome.txt", "r")print(f.read())
Read Only Parts of the File
By default the read() method returns the whole text, but you can also specify how many characters you want to return:
Example
Return the 5 first characters of the file:
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f = open("demofile.txt", "r")print(f.read(5))
You can return one line by using the readline() method:
Example
Read one line of the file:
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f = open("demofile.txt", "r")print(f.readline())
By calling readline() two times, you can read the two first lines:
Example
Read two lines of the file:
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f = open("demofile.txt", "r")print(f.readline())print(f.readline())
By looping through the lines of the file, you can read the whole file, line by line:
Example
Loop through the file line by line:
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f = open("demofile.txt", "r")for x in f: print(x)
Close Files
It is a good practice to always close the file when you are done with it.
Example
Close the file when you are finish with it:
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f = open("demofile.txt", "r")print(f.readline())f.close()
Note: You should always close your files, in some cases, due to buffering, changes made to a file may not show until you close the file.
