Excel file in C # to write data operation

C # data write operation performed on the Excel file:

First write a function

CPATH static String Private (String path) 
    { 
        var index = path.LastIndexOf ( "/"); 
        var path.Substring TEMP = (0, index); 
        (! Directory.Exists (TEMP)) // if there is no IF created file folders　　             　　               
            Directory.CreateDirectory (temp); // create the folder　　   
        return path; 
    }

Data write operation, the code used to add functions.

using (var s = new System.IO.StreamWriter(CPath("./测试.csv"), true, Encoding.GetEncoding("GB2312"), 30))

    {
        s.WriteLine($"{"列1"},{"列2"}");
    }