Csv Writing Strings Of Text That Need A Unique Delimiter

I wrote an HTML parser in python used to extract data to look like this in a csv file: itemA, itemB, itemC, Sentence that might contain commas, or colons: like this,\n so I us

Solution 1:

As I suggested informally in a comment, unique just means you need to use some character that won't be in the data — chr(255) might be a good choice. For example:

Note: The code shown is for Python 2.x — see comments for a Python 3 version.

import csv

DELIMITER = chr(255)
data = ["itemA", "itemB", "itemC",
        "Sentence that might contain commas, colons: or even \"quotes\"."]

withopen('data.csv', 'wb') as outfile:
    writer = csv.writer(outfile, delimiter=DELIMITER)
    writer.writerow(data)

withopen('data.csv', 'rb') as infile:
    reader = csv.reader(infile, delimiter=DELIMITER)
    for row in reader:
        print row

Output:

['itemA', 'itemB', 'itemC', 'Sentence that might contain commas, colons: or even "quotes".']

If you're not using the csv module and instead are writing and/or reading the data manually, then it would go something like this:

withopen('data.csv', 'wb') as outfile:
    outfile.write(DELIMITER.join(data) + '\n')

withopen('data.csv', 'rb') as infile:
    row = infile.readline().rstrip().split(DELIMITER)
    print row

Solution 2:

Yes, delimiters separate values within each line of a CSV file. There are two strategies to delimiting text that has a lot of punctuation marks. First, you can quote the values, e.g.:

Value 1, Value 2, "This value has a comma, <- right there", Value 4

The second strategy is to use tabs (i.e., '\t').

Python's built-in CSV module can both read and write CSV files that use quotes. Check out the example code under the csv.reader function. The built-in csv module will handle quotes correctly, e.g. it will escape quotes that are in the value itself.