Practical Usage of Find Generic List

Practical usage of Find<T> Method in Generic List<T> using Predicate

In this article we are going to see the Practical usage of Find<T> Method in Generic List<T> using Predicate.

Step 1:

Used Namespaces:

using System; using System.Collections.Generic;

Step 2:

Used Collection for demo:

// <summary> /// This is static collection used in this tutorials /// </summary> /// <returns></returns> private List<CompanyProduct> AddCollection() { List<CompanyProduct> list = new List<CompanyProduct>(); list.Add(new CompanyProduct("MS Word", 1, "Microsoft", new DateTime(2012, 10, 31))); list.Add(new CompanyProduct("MS Excel", 2, "Microsoft", new DateTime(2011, 10, 31))); list.Add(new CompanyProduct("MS Powerpoint", 3, "Microsoft", new DateTime(2010, 10, 31))); list.Add(new CompanyProduct("Visual Studio", 2, "Microsoft", new DateTime(2011, 10, 31))); list.Add(new CompanyProduct("Sql Server", 3, "Microsoft", new DateTime(2010, 10, 31))); list.Add(new CompanyProduct("Oracle", 4, "Oracle", new DateTime(2011, 10, 31))); list.Add(new CompanyProduct("Sharepoint", 6, "Microsoft", new DateTime(2012, 10, 31))); list.Add(new CompanyProduct("MS Outlook", 7, "Microsoft", new DateTime(2011, 10, 31))); return list; }

Step 3:

Printing the collection:

List<CompanyProduct> list = AddCollection(); PrintList(list, "Available Collection");

Filtering the first product by company name using Predicate //Filter the first product by company name. CompanyProduct cp = list.Find(delegate(CompanyProduct item) { return item.CompanyName == "Microsoft"; });

Response.Write("<br/>"); Response.Write(string.Format(" cp.Product, cp.CompanyName));

Product={0} >>> CompanyName={1}",

Step 4:

Filtering the first product by product id using Predicate

//Filter the first product by product id. cp = list.Find(delegate(CompanyProduct item) { return item.ProductID == 1; }); Response.Write("<br/>"); Response.Write(string.Format(" Product={0} >>> CompanyName={1}", cp.Product, cp.CompanyName));

Step 5:

Filtering the first product by productRegisterDate using Predicate

//Filter the first product by productRegisterDate. cp = list.Find(delegate(CompanyProduct item) { return item.ProductRegisterDate == new DateTime(2010, 10, 31); }); Response.Write("<br/>"); Response.Write(string.Format(" Product={0} >>> CompanyName={1}", cp.Product, cp.CompanyName));

Step 6:

Used for printing the results:

/// <summary> /// This is used to display the list after editing list. /// </summary> private void PrintList(List<CompanyProduct> list, string header) { Response.Write("<br/>"); Response.Write(" " + header); Response.Write("<br/>"); foreach (CompanyProduct cp in list) { //Response.Write(string.Format("Product={0} >>> ProductId={1} >>> CompanyName={2} >>> RegisterDate={3}", // cp.Product, cp.ProductID, cp.CompanyName, cp.ProductRegisterDate)); Response.Write(string.Format(" Product={0} >>> CompanyName={1}", cp.Product, cp.CompanyName)); Response.Write("<br/>"); } Response.Write("<br/>"); } }

Step 7:

Used Class for Demo

class CompanyProduct { public CompanyProduct(string product, int productID, string companyName, DateTime productRegisterDate) { this.product = product; this.productID = productID; this.companyName = companyName; this.productRegisterDate = productRegisterDate; } private string product; public string Product { get { return this.product; } set { this.product = value; } } private int productID; public int ProductID { get { return this.productID; } set { this.productID = value; } } private string companyName; public string CompanyName { get { return this.companyName; } set { this.companyName = value; } } private DateTime productRegisterDate; public DateTime ProductRegisterDate { get { return this.productRegisterDate; } set { this.productRegisterDate = value; } } }

Thanks for reading this article. Have a nice day.