Scenario: XYZ Pvt Ltd, wants to implement business logic of Delete prevention if value of Is Delete Field is No on Opportunity Entity. CRM 2013 will prevent deltetion of record if value of Is Delete Field is set to No and vice versa.
Work Around: We have added a custom field on Opportunity Entity with Display name 'Is Delete' & Schema Name 'IsDelete'.
Solution: Below is the CRM 2013 Prevent Delete Plugin code.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Microsoft.Xrm.Sdk;
using Microsoft.Xrm.Sdk.Query;
using Microsoft.Crm.Sdk.Messages;
namespace PreventAccountDelete
{
public class Class1:IPlugin
{

