How to find the number of occurrences of a string in file using windows command line?

Question

I have a huge files with e-mail addresses and I would like to count how many of them are in this file. How can I do that using Windows\' command line ?

I have tried

Answer 1

Why not simply using this (this determines the number of lines containing (at least) an @ char.):

find /C "@" "mail.txt"

Example output:

---------- MAIL.TXT: 96

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To avoid the file name in the output, change it to this:

find /C "@" < "mail.txt"

Example output:

96

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To capture the resulting number and store it in a variable, use this (change %N to %%N in a batch file):

set "NUM=0"
for /F %N in ('find /C "@" ^< "mail.txt"') do set "NUM=%N"
echo %NUM%