Read Excel using c# in Visual Studio 2015

DataTable dt = new DataTable();

SqlConnection strConnection = new SqlConnection(ConfigurationSettings.AppSettings["ConnectionString"]);

strConnection.Open();

string filepath = textBox1.Text;

string excelConnectionString = @"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + filepath + ";Extended Properties=Excel 12.0;"; //Create Connection to Excel work book

OleDbConnection excelConnection = new OleDbConnection(excelConnectionString);

excelConnection.Open();

OleDbDataAdapter da = new OleDbDataAdapter("Select [ISBN/Code],[Title],[Publisher],[Author],[Qty],[Price],[Rate In INR],[Disc%],[Value In INR],[Category] from [Sheet1$]", excelConnection);

Thread.Sleep(2000);

da.Fill(dt);

2) https://bytescout.com/products/developer/spreadsheetsdk/read-write-excel.html