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I have 2 csv file i need to merge in one file and need to remove duplicate column in merged csv file

What I have tried:

var first = File.ReadAllLines("C:\\Task\\Input\\UserInfo.csv");
            var second = File.ReadAllLines("C:\\Task\\Input\\PersonalInfo.csv");
            var result = first.Zip(second, (f, s) => string.Join(",", f, s));
            File.WriteAllLines("C:\\Divyashree\\Dot_net\\Task\\Input\\combined.csv", result);
Updated 29-Apr-21 22:14pm

1 solution

In order to do that, you first have to read your file as a CSV - and find some way to relate "row X" of file 1 with "row Y" of file 2 - then identify the duplicate columns to build a new composite dataset which you can write to a new file.

Just reading lines won't do it: that's treating CSV data as if it was a "straight text file" which it is, but that text has a layer of formatting applied which you need to utilize in order to get this to work.

And ... a CSV data column can be spread across multiple lines, if inclosed in double quotes - so you current approach will not only not allow you to identify any columns, but could seriously mess up your data integrity if you are unlucky.

I'd start by reading each CSV file into a DataTable (A Fast CSV Reader[^] could help you there) then combining them into a single new DataTable to write out to a new file.
It's a lot less effort (and more maintainable) than trying to "roll your own" CSV data reader!
Member 15088142 30-Apr-21 4:57am
can i have some sample code to do this
OriginalGriff 30-Apr-21 5:29am
Which bit?
What part did you try, and where did you get stuck?
Member 15088142 30-Apr-21 5:34am
List<string> UserInfo = new List<string>() { "Sno", "Name" };
List<string> PrsnInfo = new List<string>() { "Sno", "Gender", "State" };
var first = File.ReadAllLines("C:\\Divyashree\\Dot_net\\Task\\Input\\UserInfo.csv");
var second = File.ReadAllLines("C:\\Divyashree\\Dot_net\\Task\\Input\\PersonalInfo.csv");
created 2 list and trying to compare if exit need to remove
OriginalGriff 30-Apr-21 5:48am
So you've ignored everything I said then?
Member 15088142 30-Apr-21 5:49am
no i dont understand that
OriginalGriff 30-Apr-21 6:20am
What part doesn't make sense?

I'm not trying to be funny, or awkward - we only get to see exactly what you type, so if you don't tell us something we don't know it!

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