How to use csv.Sniffer for 2 different CSV-types?

tdhulster picture tdhulster · Feb 26, 2013 · Viewed 9.8k times · Source

I want to read 2 different types of CSV-files:

  • one with a ',' as delimiter
  • one with a ';' as delimiter

I tried to check which delimiter I'm using by doing:

dialect = csv.Sniffer().sniff(csvfile, [',', ';'])  
data = csv.reader(csvfile, dialect)

but then I get the TypeError : expected string or buffer.

If I do this, it works, but then I don't know when to use what delimiter.

data = csv.reader(csvfile, delimiter = ",")  
data = csv.reader(csvfile, delimiter = ";")

Can someone help me please?

Answer

Spencer Rathbun picture Spencer Rathbun · Feb 26, 2013

Sniffer expects a sample string, not a file. All you should need to do is:

dialect = csv.Sniffer().sniff(csvfile.readline(), [',',';'])
csvfile.seek(0)  
data = csv.reader(csvfile, dialect)

The seek is important, because you are moving your current position in the file with the readline command, and you need to reset back to the beginning of the file. Otherwise you lose data.