使用.NET中的linq计算dataGridView中列的不同值

Question

我需要在dataGridView中计算并显示不同/唯一的值.我想像这样呈现它,这个代码适用于列表.

        List<string> aryIDs = new List<string>();
        aryIDs.Add("1234");
        aryIDs.Add("4321");
        aryIDs.Add("3214");
        aryIDs.Add("1234");
        aryIDs.Add("4321");
        aryIDs.Add("1234");

        var result= aryIDs.GroupBy(id => id).OrderByDescending(id => id.Count()).Select(g => new { Id = g.Key, Count = g.Count() });

但是当我尝试在dataGridView中的列上使用相同的方法时,我得到一个错误,说groupBy不能在我的dataGridView上使用.

        DataGridView dataGridView1= new DataGridView();
        dataGridView1.Columns.Add("nr", "nr");
        string[] row1 = new string[] { "1234" };
        string[] row2 = new string[] { "4321" };
        string[] row3 = new string[] { "3214" };
        string[] row4 = new string[] { "1234" };
        string[] row5 = new string[] { "4321" };
        string[] row6 = new string[] { "1234" };

        object[] rows = new object[] { row1, row2, row3, row4, row5, row6 };

        foreach (string[] rowArray in rows)
        {
            dataGridView1.Rows.Add(rowArray);
        }

        var result = dataGridView1.GroupBy(id => id).OrderByDescending(id => id.Count()).Select(g => new { Id = g.Key, Count = g.Count() });

所以我的问题是,我如何调整这个linq语法来处理dataGridView中的列？如果可能的话,我根本不想使用列表.

Answer 1

这适用于您的示例:

var result = dataGridView1.Rows.Cast<DataGridViewRow>()
    .Where(r => r.Cells[0].Value != null)
    .Select (r => r.Cells[0].Value)
    .GroupBy(id => id)
        .OrderByDescending(id => id.Count()) 
        .Select(g => new { Id = g.Key, Count = g.Count() });

Answer 2

我认为这可以做到，但我不是 100% 确定。尝试一下，如果有任何问题请告诉我...

var distinctRows = (from GridViewRow row in dataGridView1.Rows 
                    select row.Cells[0]
                   ).Distinct().Count();