LINQ Hour 5-2 Sorting in LINQ

Written By:-Isha Malhotra 

Our Website:-www.techaltum.com

Sorting in LINQ

To sort data in LINQ we use orderby in the following manner:-

Sorting with Array

int[] marks = new int[] { 23, 45, 78, 90, 56, 89, 10, 32 };

        // it will sort in ascending order

        var sort_asc = from res_asc in marks

                       orderby res_asc

                       select res_asc;

        //it will sort in descending order

        var sort_desc = from res_desc in marks

                        orderby res_desc descending

                        select res_desc;

        Response.Write("Ascending order result <br/>");

        foreach (int res_asc in sort_asc)

        {

            Response.Write(res_asc + " ");

       

        }

        Response.Write("<br/>descending order result <br/>");

        foreach (int res_desc in sort_desc)

        {

            Response.Write(res_desc + " ");

        }

The output of the code is as follows:-

Figure 1

Sorting with Generics:-

List<data> dt = new List<data>()

        {

            new data{roll_no=1, student="isha", per=100},

            new data{roll_no=2, student="sneha", per=89},

            new data{roll_no=3, student="rahul", per=34},

            new data{roll_no=4, student="renu", per=34},

            new data{roll_no=5, student="sapna", per=89}

        };

        var res = from res_sort_asc in dt

                  orderby res_sort_asc.per

                  select res_sort_asc;

       

        Response.Write("Ascending order on the basis of Per<br/>");

       

        foreach (data res_after_sort in res)

        {

       

            Response.Write("Roll No:- "+res_after_sort.roll_no+" Student:- "+res_after_sort.student+"  per:- "+res_after_sort.per+"<br/>");

       

        }

The output of this code as follows:-

Figure 2

Similarly if we want to perform descending ordering then we will use following code:-

var res = from res_sort_asc in dt

                  orderby res_sort_asc.per descending

                  select res_sort_asc;

Sorting on the basis of more than one column

When we want to sort on the basis of more than one column then we will use following code:-

List<data> dt = new List<data>()

        {

            new data{roll_no=1, student="isha", per=100},

            new data{roll_no=2, student="sneha", per=89},

            new data{roll_no=3, student="rahul", per=34},

            new data{roll_no=4, student="renu", per=34},

            new data{roll_no=5, student="sapna", per=89}

        };

        //sort first on the basis of per then by student

        var res = from res_sort_asc in dt

                  orderby res_sort_asc.per, res_sort_asc.student

                  select res_sort_asc;

       

        Response.Write("Ascending order on the basis of Per and student<br/>");

       

        foreach (data res_after_sort in res)

        {

       

            Response.Write("Roll No:- "+res_after_sort.roll_no+" Student:- "+res_after_sort.student+"  per:- "+res_after_sort.per+"<br/>");

       

        }

The output of this code as follows:-

Figure 3

Sorting with Database

If we want to sort data on the basis of any column then we use the following code in LINQ:-

DataContext dc = new DataContext("Data Source=.;Initial Catalog=TechAltum;Integrated Security=True");

       

        var res = dc.GetTable<Class1>().OrderBy(x => x.no_of_prod);

       

        //sorting on the basis of no of pord

       

        foreach (Class1 res_data in res)

        {

       

            Response.Write("Prod Year="+res_data.prod_year+", Dept="+res_data.dept+", No_of_prod="+res_data.no_of_prod+"<br/>");

        }

The output of this code is as follows:-

Figure 4

Sorting in descending order:-

var res = dc.GetTable<Class1>().OrderByDescending(x => x.no_of_prod);

sorting on the basis of more than one columne:-

var res = dc.GetTable<Class1>().OrderByDescending(x => x.no_of_prod).ThenBy(x => x.prod_year);

Hope you enjoyed the article. For any query you can mail me at info@techaltum.com