在，有两个文本文件的情况下：

  FileA.txt
测试
1234
测试


FileB.txt
测试
5667
池塘
 

和所有出现FileA.txt将从FileB.txt被删除，被输出到FileC.txt

所以FileC.txt内容如下：

  5667
池塘
 

解决方案

  File.WriteAllLines（FileC.txt
  。File.ReadAllLines（FileB.txt）除（File.ReadAllLines（FileA.txt）））;
 

In the case that there were two text files:

FileA.txt
test
1234
testing


FileB.txt
test
5667
pond

and all occurrences in FileA.txt would be removed from FileB.txt, being output into FileC.txt

So FileC.txt would read:

5667
pond

File.WriteAllLines("FileC.txt",
  File.ReadAllLines("FileB.txt").Except(File.ReadAllLines("FileA.txt")));