How to read text file after specified line in c#

I have a huge text file which i need to read.Currently I am reading text file like this..

string[] lines = File.ReadAllLines(FileToCopy);

But here all the lines are getting being stored in lines array and after this according to the condition is being processed programtically which is not efficient way as first it will Read irrelevant rows(lines) also of the text file into array and same way will go for the processing. So my question is Can i put line number to be read from the text file..Suppose last time it had read 10001 lines and next time it should start from 10002.. How to achieve it?

Jon Skeet
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Well you don't have to store all those lines - but you definitely have to read them. Unless the lines are of a fixed length (in bytes, not characters) how would you expect to be able to skip to a particular part of the file?

To store only the lines you want in memory though, use:

List<string> lines = File.ReadLines(FileToCopy).Skip(linesToSkip).ToList();

Note that File.ReadLines() was introduced in .NET 4, and reads the lines on-demand with an iterator instead of reading the entire file into memory.

If you only want to process a certain number of lines, you can use Take as well:

List<string> lines = File.ReadLines(FileToCopy)
                         .Skip(linesToSkip)
                         .Take(linesToRead)
                         .ToList();

So for example, linesToSkip=10000 and linesToRead=1000 would give you lines 10001-11000.

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