Files in Python
-
While databases such as MySQL and Postgres are popular and widely used in many web applications, there is still a large amount to data that is stored and exchanged sing text file formats.
-
Popular formats are
- Comma Seperated Values,
- Java Script Object Notation (JSON)
- YAML
- Plain text
- Binary
-
Reading a Text file using python
- Refer Here for the sample to read the whole contents of the file
-
Read Partial content from a text file
-
With Statement for opening the files: In python we can use with block to open the files, The advantage of using this approach is as soon as the block is executed, file will be closed automatically.
- Refer Here for the changeset containing with statements
-
Writing files:
- In python we use open function to open the file and while opening the file we can specify the mode.
- Python has following file opening modes
- r: This is default mode and it opens file for reading
- w: The Write mode. This opens a file for writing, creates a new file if the file doesnot exist and overrites the contents if the file already exists
- x: This creates a new file. This operation fails if the file exists
- a: This opens file in append mode and creates the new file if a file does not exist
- b: This opens a file in binary mode
- Lets try to write a program which asks the user to enter the name, course etc and stores the data in a text file. Refer Here
- Enhance this code by doing the following
1. Add new enquiry information 2. Print all the data 3. quit Enter your choice? (1 or 2)
- Refer Here for basic skeleton.