System.Data.Tests.DataSetTest2.Relations C# (CSharp) Method

        public void Relations()
        {
            DataTable dtChild1, dtChild2, dtParent;
            var ds = new DataSet();
            //Create tables
            dtChild1 = DataProvider.CreateChildDataTable();
            dtChild1.TableName = "Child";
            dtChild2 = DataProvider.CreateChildDataTable();
            dtChild2.TableName = "CHILD";
            dtParent = DataProvider.CreateParentDataTable();
            //Add tables to dataset
            ds.Tables.Add(dtChild1);
            ds.Tables.Add(dtChild2);

            ds.Tables.Add(dtParent);

            DataRelation drl = new DataRelation("Parent-Child", dtParent.Columns["ParentId"], dtChild1.Columns["ParentId"]);
            DataRelation drl1 = new DataRelation("Parent-CHILD", dtParent.Columns["ParentId"], dtChild2.Columns["ParentId"]);

            // Checking Relations - default value
            //Check default
            Assert.Equal(0, ds.Relations.Count);

            ds.Relations.Add(drl);

            // Checking Relations Count
            Assert.Equal(1, ds.Relations.Count);

            // Checking Relations Value
            Assert.Equal(drl, ds.Relations[0]);

            // Checking Relations - get by name
            Assert.Equal(drl, ds.Relations["Parent-Child"]);

            // Checking Relations - get by name case sensetive
            Assert.Equal(drl, ds.Relations["PARENT-CHILD"]);

            // Checking Relations Count 2
            ds.Relations.Add(drl1);
            Assert.Equal(2, ds.Relations.Count);

            // Checking Relations - get by name case sensetive,ArgumentException
            Assert.Throws<ArgumentException>(() => ds.Relations["PARENT-CHILD"]);
        }