How to insert double quote ("") data with comma into one column while CSV file to datatable using in C# ?

CSV Data is pretty primitive, but it can cope with most things. If you want a comma, a newline or a double quote in a field in CSV data, teh whole field needs to be encased in double quotes:

123, Hello there, "A comma, in a field", 666

Which gives you four fields:

123
Hello there
A comma, in a field
666

Inside the double quotes you can include a double quote, but escaping it with a second one:

123, Hello there, "Some ""quoted text""", 666

Which also gives you four fields:

123
Hello there
Some "quoted text"
666

If you want to include that in a C# string literal, then you need to add the C# escapes as well:

string csvData = "123, Hello there, \"Some \"\"quoted text\"\"\", 666";

Or worse:

string csvData = @"123, Hello there, ""Some """"quoted text"""""", 666";