How to Update an item in a list by LINQ

Question

I have a list of class objects.This Class object comprise of 3 string properties.Using LINQ i am able to query the list now i want to update one of the properties of any class objects Any help will be highly appreciated.Thanks

anil babu · Answer

List Employee > empList = new List Employee > { new Employee () { EmpNo = 101  EmpName = Anil  AllDepart = new List Department > { new Department (){ DeptNo = 1  Dname = Sales  Location = Vij }} DeptName = DEV  AllSales = new List Sales > { new Sales (){ SName = jjj  Sloc = ban  Orders = new List Order >{ new Order (){ Oid = 200  OName = ebay }}}} Purchages = new List Purchage > { new Purchage () { Id = 200  IName = Mobiles } //new Department (){ DeptNo=2Dname=DEvLocation=Gun} //new Department (){ DeptNo=3Dname=proLocation=Ong} }} }; } public static class LinqUpdates { public static void Update (this IEnumerable source Action action) { foreach (var item in source) action(item); } } i WANT TO UPDATE THE ABOVE LIST USING THE BELOW METHOS HOW? i AM TRYING THIS WAY NOT POSSIBLE Method is public void Update ( Employee obj ) { var list = loadList ; loadList . Where ( p => p . EmpNo == obj . EmpNo ). Update (); } how to modify my method?

Subhendu De · Answer

Yes you can but you need to write the extension method for it. Dont worry Troy Magennis had written it. I used that extension method. The link is http://www.hookedonlinq.com/UpdateOperator.ashx Please go through the code. If you need any other info please let me know. using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Data.Linq; using System.IO; using System.Threading; using System.Data.SqlClient; namespace PracticeConsole { class Program { static void Main(string[] args) { Student[] _arrStudents = new Student[] { new Student(AAA1A) new Student(BBB2B) new Student(CCC3C) new Student(DDD4D) new Student(EEE5E) new Student(FFF6F) new Student(GGG7G) new Student(HHH8H) new Student(III9I) }; Console.WriteLine(Before update); foreach (Student _student in _arrStudents) { Console.WriteLine(String.Format({0}{1}{2} _student.Name _student.Standard _student.Status)); } var query = (from stud in _arrStudents where stud.Name == BBB select stud) .Update(st => { st.Standard = 0; st.Status = X; }); Console.WriteLine(After update); foreach (Student _student in _arrStudents) { Console.WriteLine(String.Format({0}{1}{2}_student.Name_student.Standard_student.Status)); } } } class Student { public string Name { get; set; } public string Standard { get; set; } public string Status { get; set; } public Student(string name string standard string status) { this.Name = name; this.Standard = standard; this.Status = status; } } public static class UpdateExtensions { public delegate void Func (TArg0 element); public static int Update (this IEnumerable source Func update) { if (source == null) throw new ArgumentNullException(source); if (update == null) throw new ArgumentNullException(update); if (typeof(TSource).IsValueType) throw new NotSupportedException(value type elements are not supported by update.); int count = 0; foreach (TSource element in source) { update(element); count++; } return count; } } }