In this article we will discuss about how to open a file using ‘open with’ statement, how to open multiple files in a single ‘open with’ statement and finally its benefits. So, let’s start the topic.<\/p>\n
To understand the \u201copen with\u201d statement we have to go through opening a file in python. For that we can make use of the File.txt-<\/strong><\/p>\n In case the file does not exist it will throw a The With \u201cwith\u201d statement we don’t have to close the opened file manually. It takes care of that when the compiler goes out of the block and automatically closes file. So it reduces the chances of bugs, lines of code and releases the memory for other operations.<\/p>\n If we have used \u201copen-with\u201d statement to open a file, and an exception occurs inside the with block, the file will be closed and the control moves to the except block.<\/p>\nopen( )<\/code> function that is in-built in python<\/p>\nNew File Being Read.\r\nDONE!!<\/pre>\n
#program :\r\n\r\n# opened a file \r\nfileObj = open('file.txt')\r\n# Reading the file content into a placeholder\r\ndata = fileObj.read()\r\n# print file content\r\nprint(data)\r\n#close the file\r\nfileObj.close()\r\n<\/pre>\nOutput :\r\nNew File Being Read.\r\nDONE!!<\/pre>\n
FileNotFoundError<\/code> .<\/p>\nHow to open a file using \u201copen with\u201d statement in python :<\/h3>\n
#Program :\r\n\r\n# opened a file using open-with\r\nwith open('file.txt', \"r\") as fileObj:\r\n # Reading the file content into a placeholder\r\n data = fileObj.read()\r\n # print file content\r\n print(data)\r\n# Check if file is closed\r\nif fileObj.closed == False:\r\n print('File is not closed')\r\nelse:\r\n print('File is already closed')\r\n<\/pre>\nNew File Being Read.\r\nDONE!!\r\nFile is closed\r\n<\/pre>\n
with<\/code> statements created an execution block that will automatically delete any object that was created in the program, in this case even if it was not closed the reader object was deleted that closed the file automatically. This saves us some memory in case we forgot to close the file.<\/p>\nBenefits of calling open() using \u201cwith statement\u201d :<\/h3>\n
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Fewer chances of bug due to coding error<\/h4>\n<\/li>\n<\/ul>\n
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Excellent handling in case of exception<\/h4>\n<\/li>\n<\/ul>\n
# Python :\r\n\r\n# Before handling the exception file\u00a0will\u00a0be\u00a0closed\u00a0\r\ntry:\r\n # using \"with statement\" with open() function\r\n with open('file.txt', \"r\") as fileObj:\r\n # reading the file content\r\n data = fileObj.read()\r\n # Division by zero error\r\n x = 1 \/ 0\r\n print(data)\r\nexcept:\r\n # handling the exception caused above\r\n print('Error occurred')\r\n if fileObj.closed == False:\r\n print('File is not closed')\r\n else:\r\n print('File is closed')\r\n<\/pre>\nOutput :\r\nError occurred\r\nFile is closed<\/pre>\n