title: How to compare only date part with linq expression?
body: <p>I just want to make Column Filter for grid view. Simple I just want to filter grid view column with some extra stuff. Here I have created one IQueryable that returns queryable result.</p>
  
  <p>Here is my code :</p>
  
  <p><strong>------------------------------------------Updated------------------------------------------------</strong></p>
  
  <pre><code>public static IQueryable&lt;T&gt; FilterForColumn&lt;T&gt;(this IQueryable&lt;T&gt; queryable, string colName, string searchText)
  {
      if (colName != null &amp;&amp; searchText != null)
      {
          var parameter = Expression.Parameter(typeof(T), "m");
          var propertyExpression = Expression.Property(parameter, colName);
          System.Linq.Expressions.ConstantExpression searchExpression = null;
          System.Reflection.MethodInfo containsMethod = null;
          System.Linq.Expressions.MethodCallExpression body = null;
          System.Nullable&lt;DateTime&gt; nextDate = null;
          Expression ex1 = null;
          Expression ex2 = null;
          switch (colName)
          {
              case "JobID":
              case "FileSize":
              case "TotalFileSize":
                  Int64? size = Convert.ToInt64(searchText);
                  searchExpression = Expression.Constant(searchText);
                  containsMethod = typeof(Int64?).GetMethod("Equals", new[] { typeof(Int64?) });
                  body = Expression.Call(propertyExpression, containsMethod, searchExpression);
                  break;
              case "PublishDate":
              case "Birth_date":
              case "Anniversary_date":
              case "Profile_Updated_datetime":
              case "CompletedOn":
                  DateTime? currentDate = DateTime.ParseExact(searchText, "dd/MM/yyyy", null);
                  nextDate = currentDate.Value.AddDays(1);
                  ex1 = Expression.GreaterThanOrEqual(propertyExpression, Expression.Constant(currentDate));
                  ex2 = Expression.LessThan(propertyExpression, Expression.Constant(nextDate));
                  body = Expression.AndAlso(ex1, ex2);
                  break;
              case "Created_datetime":
              case "Reminder_Date":
              case "News_date":
              case "thought_date":
              case "SubscriptionDateTime":
              case "Register_datetime":
              case "CreatedOn":
                  DateTime dt1 = DateTime.ParseExact(searchText, "dd/MM/yyyy", null);
                  nextDate = currentDate.Value.AddDays(1);
                  ex1 = Expression.GreaterThanOrEqual(propertyExpression, Expression.Constant(currentDate));
                  ex2 = Expression.LessThan(propertyExpression, Expression.Constant(nextDate));
                  body = Expression.AndAlso(ex1, ex2);
                  break;
              default :
                  searchExpression = Expression.Constant(searchText);
                  containsMethod = typeof(string).GetMethod("Contains", new[] { typeof(string) });
                  body = Expression.Call(propertyExpression, containsMethod, searchExpression);
                  break;
          }
          var predicate = Expression.Lambda&lt;Func&lt;T, bool&gt;&gt;(body, new[] { parameter });
          return queryable.Where(predicate);
      }
      else
      {
          return queryable;
      }
  }
  </code></pre>
  
  <p>here this solution gives some compile time error :</p>
  
  <pre><code>Error   9   Cannot implicitly convert type 'System.Linq.Expressions.BinaryExpression' to 'System.Linq.Expressions.MethodCallExpression' F:\EasyWeb\App_Code\Helper.cs   47  28  F:\EasyWeb\
  </code></pre>
  
  <p>Here at case of DateTime I just want to filter DateTime column with only Date not whole DATETIME value.</p>
  
  <p>Here I just put required things :</p>
  
  <pre><code>SELECT [t8].[Id], [t8].[Title], [t8].[value] AS [Publisher], [t8].[value2] AS [ToUser], [t8].[Sent_Datetime] AS [PublishDate], [t8].[IsFileAttached] AS [IsFile], [t8].[Category_name] AS [CategoryName], [t8].[value3] AS [status_name], [t8].[value4] AS [Group_name], [t8].[TotalFileSize] AS [FileSize]
  FROM (
      SELECT [t0].[Id], [t0].[Title], (
          SELECT TOP (1) [t3].[value]
          FROM (
              SELECT ([t2].[First_name] + ' ') + [t2].[Last_name] AS [value], [t2].[Id]
              FROM [dbo].[tbl_User_master] AS [t2]
              ) AS [t3]
          WHERE [t3].[Id] = [t0].[User_id]
          ) AS [value], (
          SELECT TOP (1) [t5].[value]
          FROM (
              SELECT ([t4].[First_name] + ' ') + [t4].[Last_name] AS [value], [t4].[Id]
              FROM [dbo].[tbl_User_master] AS [t4]
              ) AS [t5]
          WHERE ([t5].[Id]) = [t0].[ToUser_id]
          ) AS [value2], [t0].[Sent_Datetime], [t0].[IsFileAttached], [t1].[Category_name], (
          SELECT TOP (1) [t6].[status_name]
          FROM [dbo].[tbl_status_master] AS [t6]
          WHERE ([t6].[Id]) = [t0].[status_id]
          ) AS [value3], (
          SELECT TOP (1) [t7].[Group_name]
          FROM [dbo].[tbl_Group_master] AS [t7]
          WHERE ([t7].[Id]) = [t0].[group_id]
          ) AS [value4], [t0].[TotalFileSize], [t0].[ToUser_id], [t0].[User_id]
      FROM [dbo].[tbl_Post_History] AS [t0]
      INNER JOIN [dbo].[tbl_Category_master] AS [t1] ON [t0].[Category_id] = [t1].[Id]
      ) AS [t8]
  WHERE (CAST(CONVERT(CHAR(10), [t8].[Sent_Datetime], 102) AS DATETIME) = '12/24/2013' ) AND (([t8].[ToUser_id] = 3) OR ([t8].[ToUser_id] IS NULL)) AND ([t8].[User_id] &lt;&gt; 3)
  ORDER BY [t8].[Sent_Datetime] DESC
  </code></pre>
  
  <p>Here this shows required output or logic that we will do with queryable.</p>
  
  <p>But, here one drawback occurs while this method <code>Equals</code> check whole Date Time. 
  Is that possible with this method to force only check Date Part from column?</p>
  
  <p><strong>------------------------------------2-Updated-----------------------------------------</strong></p>
  
  <p>for overwhelming this problem i use this technique :</p>
  
  <pre><code> public static IQueryable&lt;T&gt; FilterForColumn&lt;T&gt;(this IQueryable&lt;T&gt; queryable, string colName, string searchText)
      {
          if (colName != null &amp;&amp; searchText != null)
          {
              var parameter = Expression.Parameter(typeof(T), "m");
              var propertyExpression = Expression.Property(parameter, colName);
              System.Linq.Expressions.ConstantExpression searchExpression = null;
              System.Reflection.MethodInfo containsMethod = null;
              System.Linq.Expressions.BinaryExpression body = null;
              DateTime? currentDate = null;
              DateTime? nextDate = null;
              Expression ex1 = null;
              Expression ex2 = null;
              switch (colName)
              {
                  case "JobID":
                  case "FileSize":
                  case "TotalFileSize":
                      Int64? size = Convert.ToInt64(searchText);
                      searchExpression = Expression.Constant(searchText);
                      containsMethod = typeof(Int64?).GetMethod("Equals", new[] { typeof(Int64?) });
                      //body = Expression.Call(propertyExpression, containsMethod, searchExpression);
                      break;
                  case "PublishDate":
                  case "Birth_date":
                  case "Anniversary_date":
                  case "Profile_Updated_datetime":
                  case "CompletedOn":
                      currentDate = DateTime.ParseExact(searchText, "dd/MM/yyyy", null);
                      nextDate = currentDate.Value.AddDays(1);
                      ex1 = Expression.GreaterThanOrEqual(propertyExpression, Expression.Constant(currentDate));
                      ex2 = Expression.LessThan(propertyExpression, Expression.Constant(nextDate));
                      body = Expression.AndAlso(ex1, ex2);
                      break;
                  case "Created_datetime":
                  case "Reminder_Date":
                  case "News_date":
                  case "thought_date":
                  case "SubscriptionDateTime":
                  case "Register_datetime":
                  case "CreatedOn":
                      currentDate = DateTime.ParseExact(searchText, "dd/MM/yyyy", null);
                      nextDate = currentDate.Value.AddDays(1);
                      ex1 = Expression.GreaterThanOrEqual(propertyExpression, Expression.Constant(currentDate));
                      ex2 = Expression.LessThan(propertyExpression, Expression.Constant(nextDate));
                      body = Expression.AndAlso(ex1, ex2);
                      break;
                  default :
                      searchExpression = Expression.Constant(searchText);
                      containsMethod = typeof(string).GetMethod("Contains", new[] { typeof(string) });
                      //body = Expression.Call(propertyExpression, containsMethod, searchExpression);
                      break;
              }
              var predicate = Expression.Lambda&lt;Func&lt;T, bool&gt;&gt;(body, new[] { parameter });
              return queryable.Where(predicate);
          }
          else
          {
              return queryable;
          }
      }
  </code></pre>
  
  <p>it's give me run time error like :</p>
  
  <pre><code>Server Error in '/EasyWeb' Application.
  
  The binary operator GreaterThanOrEqual is not defined for the types 'System.Nullable`1[System.DateTime]' and 'System.DateTime'.
  
  Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code. 
  
  Exception Details: System.InvalidOperationException: The binary operator GreaterThanOrEqual is not defined for the types 'System.Nullable`1[System.DateTime]' and 'System.DateTime'.
  
  Source Error: 
  
  
  Line 44:                     currentDate = DateTime.ParseExact(searchText, "dd/MM/yyyy", null);
  Line 45:                     nextDate = currentDate.Value.AddDays(1);
  Line 46:                     ex1 = Expression.GreaterThanOrEqual(propertyExpression, Expression.Constant(currentDate));
  Line 47:                     ex2 = Expression.LessThan(propertyExpression, Expression.Constant(nextDate));
  Line 48:                     body = Expression.AndAlso(ex1, ex2);
  
  Source File: f:\EasyWeb\App_Code\Helper.cs    Line: 46 
  
  Stack Trace: 
  
  
  [InvalidOperationException: The binary operator GreaterThanOrEqual is not defined for the types 'System.Nullable`1[System.DateTime]' and 'System.DateTime'.]
     System.Linq.Expressions.Expression.GetUserDefinedBinaryOperatorOrThrow(ExpressionType binaryType, String name, Expression left, Expression right, Boolean liftToNull) +752213
     System.Linq.Expressions.Expression.GetComparisonOperator(ExpressionType binaryType, String opName, Expression left, Expression right, Boolean liftToNull) +221
     System.Linq.Expressions.Expression.GreaterThanOrEqual(Expression left, Expression right, Boolean liftToNull, MethodInfo method) +53
     System.Linq.Expressions.Expression.GreaterThanOrEqual(Expression left, Expression right) +8
     Helper.FilterForColumn(IQueryable`1 queryable, String colName, String searchText) in f:\EasyWeb\App_Code\Helper.cs:46
     Admin_Post_History.FillGrid(String CommandName, String ColumnName, String SearchText) in f:\EasyWeb\Admin\Post_History.aspx.cs:79
     Admin_Post_History.btnsearch_Click(Object sender, EventArgs e) in f:\EasyWeb\Admin\Post_History.aspx.cs:2375
     System.Web.UI.WebControls.Button.OnClick(EventArgs e) +111
     System.Web.UI.WebControls.Button.RaisePostBackEvent(String eventArgument) +110
     System.Web.UI.WebControls.Button.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument) +10
     System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument) +13
     System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData) +36
     System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +1565
  
  Version Information: Microsoft .NET Framework Version:2.0.50727.3053; ASP.NET Version:2.0.50727.3053
  </code></pre>
  
  <p><strong>-------------------------------- 3 Update-------------------------------------------</strong></p>
  
  <p>here is what i'm querying :</p>
  
  <pre><code>case "Inbox":
                          lbl_disply.Text = "Inbox";
                          lbut_showinbox.Font.Bold = true;
                          lbut_showoutbox.Font.Bold = false;
                          lbut_showdraffs.Font.Bold = false;
                          lbut_showtrash.Font.Bold = false;
                          var query1 = db.Posts.Where(p =&gt; (p.ToUser_id.Equals(user_id) || p.ToUser_id.Equals(null)) &amp;&amp; p.User_id != user_id).OrderByDescending(p=&gt;p.Sent_Datetime).Select(p =&gt; new
                          {
                              Id = p.Id,
                              Title = p.Title,
                              Publisher = db.Users.Where(u =&gt; u.Id.Equals(p.User_id)).Select(u =&gt; u.First_name + ' ' + u.Last_name).FirstOrDefault(),
                              ToUser = db.Users.Where(u =&gt; u.Id.Equals(p.ToUser_id)).Select(u =&gt; u.First_name + ' ' + u.Last_name).FirstOrDefault(),
                              PublishDate = p.Sent_Datetime,
                              IsFile = p.IsFileAttached,
                              CategoryName = db.Categories.Where(c =&gt; c.Id.Equals(p.Category_id)).Select(c =&gt; c.Category_name).FirstOrDefault(),
                              status_name = db.Status.Where(s =&gt; s.Id.Equals(p.status_id)).Select(s =&gt; s.status_name).FirstOrDefault(),
                              Group_name = db.Groups.Where(g =&gt; g.Id.Equals(p.group_id)).Select(g =&gt; g.Group_name).FirstOrDefault(),
                              FileSize = p.TotalFileSize
                          }).FilterForColumn(ColumnName, SearchText).ToList();
  </code></pre>
  
  <p>at grid view filling </p>
  
  <pre><code>DataSet myDataSet = new DataSet();
                          DataTable dt = new DataTable();
                          dt.Columns.Add(new DataColumn("Id", typeof(int)));
                          dt.Columns.Add(new DataColumn("IsRead", typeof(bool)));
                          dt.Columns.Add(new DataColumn("IsImp", typeof(bool)));
                          dt.Columns.Add(new DataColumn("Title", typeof(string)));
                          dt.Columns.Add(new DataColumn("Publisher", typeof(string)));
                          dt.Columns.Add(new DataColumn("ToUser", typeof(string)));
                          dt.Columns.Add(new DataColumn("PublishDate", typeof(DateTime?)));
                          dt.Columns.Add(new DataColumn("IsFile", typeof(bool)));
                          dt.Columns.Add(new DataColumn("CategoryName", typeof(string)));
                          dt.Columns.Add(new DataColumn("status_name", typeof(string)));
                          dt.Columns.Add(new DataColumn("Group_name", typeof(string)));
                          dt.Columns.Add(new DataColumn("FileSize", typeof(string)));
                          foreach (var item in query1)
  </code></pre>
  
  <p>i declared this PublishDate as typeof(DateTime?) but this gives me run time error like :</p>
  
  <pre><code>Server Error in '/EasyWeb' Application.
  
  DataSet does not support System.Nullable&lt;&gt;.
  
  Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code. 
  
  Exception Details: System.NotSupportedException: DataSet does not support System.Nullable&lt;&gt;.
  
  Source Error: 
  
  
  Line 101:                        dt.Columns.Add(new DataColumn("Publisher", typeof(string)));
  Line 102:                        dt.Columns.Add(new DataColumn("ToUser", typeof(string)));
  Line 103:                        dt.Columns.Add(new DataColumn("PublishDate", typeof(DateTime?)));
  Line 104:                        dt.Columns.Add(new DataColumn("IsFile", typeof(bool)));
  Line 105:                        dt.Columns.Add(new DataColumn("CategoryName", typeof(string)));
  
  Source File: f:\EasyWeb\Admin\Post_History.aspx.cs    Line: 103 
  
  Stack Trace: 
  
  
  [NotSupportedException: DataSet does not support System.Nullable&lt;&gt;.]
     System.Data.DataColumn..ctor(String columnName, Type dataType, String expr, MappingType type) +4826536
     System.Data.DataColumn..ctor(String columnName, Type dataType) +12
     Admin_Post_History.FillGrid(String CommandName, String ColumnName, String SearchText) in f:\EasyWeb\Admin\Post_History.aspx.cs:103
     Admin_Post_History.Page_Load(Object sender, EventArgs e) in f:\EasyWeb\Admin\Post_History.aspx.cs:59
     System.Web.Util.CalliHelper.EventArgFunctionCaller(IntPtr fp, Object o, Object t, EventArgs e) +14
     System.Web.Util.CalliEventHandlerDelegateProxy.Callback(Object sender, EventArgs e) +35
     System.Web.UI.Control.OnLoad(EventArgs e) +99
     System.Web.UI.Control.LoadRecursive() +50
     System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +627
  
  Version Information: Microsoft .NET Framework Version:2.0.50727.3053; ASP.NET Version:2.0.50727.3053
  </code></pre>
  
  <p><strong>---------------------------------4 Update----------------------------------------</strong></p>
  
  <p>i check my dbml file and this is screen shot for verify that it's nullable</p>
  
  <p><img src="https://i.stack.imgur.com/jKNKM.png" alt="enter image description here"></p>