Initial Commit

TestConsoleApp/Program.cs

@@ -0,0 +1,88 @@
+using System.Linq.Expressions;
+using System.Reflection;
+
+TestClassRepo repo = new();
+
+var test = repo.Get(_ => _.Name == "Test" || _.Id == "TestId2");
+
+var testexpression = repo.Get(filter: [ new() { Name = "Test2", Description = "Test2" }]);
+
+Console.WriteLine(test);
+
+Console.ReadLine();
+
+public class TestClass
+{
+    public string Name { get; set; }
+    public string Id { get; set; }
+    public string Description { get; set; }
+    public bool? IsActive { get; set; }
+}
+
+public class TestClassRepo
+{
+    private List<TestClass> _list = [new() { Name = "Test" , Id = "TestId" }, new() { Name = "Test2" , Id = "TestId2", Description = "Test2" }, new() { Name = "Test3" , Id = "Test3" } ];
+    
+    public List<TestClass> Get(Predicate<TestClass>? predicate = null, List<TestClass>? filter = null)
+    {
+        if (predicate != null)
+        {
+            return TestUtils.Get<TestClass>(predicate, _list);  
+        }
+        else if (filter != null)
+        {
+            return TestUtils.GetFilter<TestClass>(filter, _list);
+        }
+        
+        return _list;
+    }
+}
+
+public class TestUtils
+{
+    public static List<T> Get<T>(Predicate<T> predicate, IEnumerable<T> collection)
+    {
+        List<T> result = [];
+        
+        foreach (var item in collection)
+        {
+            if (predicate(item))
+            {
+                result.Add(item);
+            }
+        }
+        
+        return result;
+    }
+
+    public static List<T> GetFilter<T>(List<T> obj, List<T> collection)
+    {
+        ParameterExpression param = Expression.Parameter(typeof(T));
+        Expression predicate = Expression.Constant(true);
+        
+        foreach (var item in obj)
+        {
+            PropertyInfo[] properties = typeof(T).GetProperties();
+
+            foreach (PropertyInfo property in properties)
+            {
+                string name = property.Name;
+                var value = property.GetValue(item);
+
+                if (value is not null)
+                {
+                    MemberExpression propertyExpression = Expression.Property(param, name);
+                
+                    ConstantExpression constant = Expression.Constant(value);
+                
+                    BinaryExpression body = Expression.Equal(propertyExpression, constant);
+                
+                    predicate = Expression.AndAlso(predicate, body);
+                }
+            }
+        }
+
+        var lambda = Expression.Lambda<Func<T, bool>>(predicate, param);
+        return collection.Where(lambda.Compile()).ToList();
+    }
+}