根据字符的ascii（或unicode）代码对DataTable进行排序

Question

I have a DataTable with data in a string column. Values: "1" "{" "2"

When I select data from the DataTable sorting by the column I would like to get the values as: "1" "2" "{"

but instead, I get the values as: "{" "1" "2"

If I needed to do it in sql server I would use the collation "Latin1_general_bin". I need that same behavior in DataTable.

Here is my test:

 [Test]
    public void TestDataTable()
    {
        var dt = new DataTable();
        dt.Columns.Add("a", typeof(string));
        dt.Rows.Add("1");
        dt.Rows.Add("{");
        dt.Rows.Add("2");
        int i = 0;
        foreach (var val in dt.Select("", "a"))
        {
            Assert.AreEqual(new string[] {"1", "2", "{"}[i++],val["a"]);
        }
    }

Answer 1

You can turn the DataTable into an Enumerable and then use OrderBy. Then use Enumerable.AsDataView().Table.

Might be a bit much, but it should work.

Cheers, Lior :).

Answer 2

The best solution I can come up with at this time is, setting the private field _compareFlags using reflection. I know, I hate reflection for this, and it might stop working at some unknown time, but I have a lot of unit tests for it so I hope I will not live to regret this.

Any better solution is welcome, I thought of creating my own culture info, but couldn't see it through (open to suggestions on this path).

Here is what I did with reflection:

 [Test]
    public void TestDataTable()
    {
        var dt = new DataTable();
        var f = typeof (DataTable).GetField("_compareFlags",
                                            System.Reflection.BindingFlags.NonPublic |
                                            System.Reflection.BindingFlags.Instance);

        var v = (System.Globalization.CompareOptions) f.GetValue(dt);
        f.SetValue(dt,  CompareOptions.OrdinalIgnoreCase);



        dt.Columns.Add("a", typeof(string));
        dt.Rows.Add("1");
        dt.Rows.Add("{");
        dt.Rows.Add("2");
        int i = 0;
        foreach (var val in dt.Select("", "a"))
        {
            Assert.AreEqual(new string[] {"1", "2", "{"}[i++],val["a"]);
        }
    }