I have a datatable that will consist of 72 columns.

I will download it in the excel sheet using VSTO, which works fine.

Now the user will change either one of these rows or all of these rows and will also insert a fresh row.

Considering the datatable downloaded first to be dtA, and the one that has been modified in the excel sheet to be dtB.

I want to compare dtA and dtB.

I need to find out all the rows in dtB that do not exist in dtA.

I cant put foreach loop for each and every single row and evaluate as its a very untidy way of coding.

What is a better way to do this?

I did this way,

    DataTable dtA = new DataTable();
    dtA.Columns.Add("ENo");
    dtA.Columns.Add("ENo1");
    dtA.Columns.Add("ENo2");
    dtA.Columns.Add("ENo3");
    dtA.Columns.Add("ENo4");

    for (int i = 0; i < 5; i++)
    {
        DataRow dr = dtA.NewRow();
        dr[0] = "Part 0 " + i.ToString();
        dr[1] = "Part 1 " + i.ToString();
        dr[2] = "Part 2 " + i.ToString();
        dr[3] = "Part 3 " + i.ToString();
        dr[4] = "Part 4 " + i.ToString();
        dtA.Rows.Add(dr);
    }

    DataTable dtB = new DataTable();
    dtB.Columns.Add("ENo");
    dtB.Columns.Add("ENo1");
    dtB.Columns.Add("ENo2");
    dtB.Columns.Add("ENo3");
    dtB.Columns.Add("ENo4");

    for (int i = 5; i < 10; i++)
    {
        DataRow dr = dtB.NewRow();
        dr[0] = "Part 0 " + i.ToString();
        dr[1] = "Part 1 " + i.ToString();
        dr[2] = "Part 2 " + i.ToString();
        dr[3] = "Part 3 " + i.ToString();
        dr[4] = "Part 4 " + i.ToString();
        dtB.Rows.Add(dr);
    }

    Response.Write("\n");
    Response.Write("dt A");
    Response.Write("\n");

    for (int i = 0; i < dtA.Rows.Count; i++)
    {
        Response.Write(dtA.Rows[i][i].ToString());
        Response.Write("\n");
    }

    Response.Write("\n");
    Response.Write("dt B");
    Response.Write("\n");
    for (int i = 0; i < dtB.Rows.Count; i++)
    {
        Response.Write(dtB.Rows[i][i].ToString());
        Response.Write("\n");
    }

    var VarA = dtA.AsEnumerable();
    var varB = dtA.AsEnumerable();

    var diff = VarA.Except(varB);
    Response.Write("except");
    foreach (var n in diff)
    {
        Response.Write(n.Table.Rows[0].ToString());

    }

But I do not know what to use in the foreach var, What should I use pls?