Problem in using Lambda expressions

Question

Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable{mso-style-name:Table Normal;mso-tstyle-rowband-size:0;mso-tstyle-colband-size:0;mso-style-noshow:yes;mso-style-priority:99;mso-style-qformat:yes;mso-style-parent:;mso-padding-alt:0in 5.4pt 0in 5.4pt;mso-para-margin:0in;mso-para-margin-bottom:.0001pt;mso-pagination:widow-orphan;font-size:11.0pt;font-family:Calibrisans-serif;mso-ascii-font-family:Calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:Times New Roman;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:Calibri;mso-hansi-theme-font:minor-latin;mso-bidi-font-family:Times New Roman;mso-bidi-theme-font:minor-bidi;} Hi all I have a problem and need help to address this urgent requirement. The data in the database table resembles like the as below. ID Name 1001 john 1002 davis 1003 name 1002 name 1001 johny 1003 mani 1003 ganesh I need to show the string in the table like below using c# linq ID Name 1001 John johny 1002 Davis name 1003 Name mani ganesh or 1001 = john Johnny 1002 = davis name 1003 = name mani ganesh Any kind of solution to this problem is greatly appreciated. Thanks in advance. Regards Rajesh

Vulpes · Answer

Here's some basic LINQ code to do that: using System; using System.Collections.Generic; using System.Linq; class Person { public int ID {get; set;} public string Name {get; set;} public Person(int id string name) { ID = id; Name = name; } public override string ToString() { return String.Format({0} = {1} ID Name); } } class Program { static void Main() { Person[] persons = new Person[7] { new Person(1001 john) new Person(1002 davis) new Person(1003 name) new Person(1002 name) new Person(1001 johny) new Person(1003 mani) new Person(1003 ganesh) }; var query = persons.GroupBy(p => p.ID).OrderBy(g => g.Key); var list = new List (); foreach(var g in query) { var names = new List (); foreach(Person p in g) names.Add(p.Name); Person combined = new Person(g.Key String.Join(  names.ToArray())); list.Add(combined); } // print out combined results foreach(Person p in list) Console.WriteLine(p); Console.ReadKey(); } }

Jignesh Trivedi · Answer

hi you can also doing same thing using Lamba expression try List persons = new List (); persons.Add(new Person { ID = 1001 Name = john }); persons.Add(new Person { ID = 1002 Name = davis }); persons.Add(new Person { ID = 1003 Name = name }); persons.Add(new Person { ID = 1002 Name = name }); persons.Add(new Person { ID = 1001 Name = johny }); persons.Add(new Person { ID = 1003 Name = mani }); persons.Add(new Person { ID = 1003 Name = ganesh }); var test = from p in persons group p by new { p.ID } into a select new { ID = a.Key.ID Name = string.Join( persons.Where(f => f.ID == a.Key.ID).Select(g => g.Name).ToArray()) }; hope this help.

ID	Name
1001	john
1002	davis
1003	name
1002	name
1001	johny
1003	mani
1003	ganesh

ID	Name
1001	John, johny
1002	Davis, name
1003	Name, mani, ganesh