diff --git a/Src/Asp.NetCore2/SqlSugar/Realization/Dm/SqlBuilder/DmExpressionContext.cs b/Src/Asp.NetCore2/SqlSugar/Realization/Dm/SqlBuilder/DmExpressionContext.cs
index ad55b0b93..005e27e63 100644
--- a/Src/Asp.NetCore2/SqlSugar/Realization/Dm/SqlBuilder/DmExpressionContext.cs
+++ b/Src/Asp.NetCore2/SqlSugar/Realization/Dm/SqlBuilder/DmExpressionContext.cs
@@ -53,12 +53,7 @@ namespace SqlSugar
         }
     }
     public partial class DmMethod : DefaultDbMethod, IDbMethods
-    {
-        //public override string IsNullOrEmpty(MethodCallExpressionModel model)
-        //{
-        //    var parameter = model.Args[0];
-        //    return string.Format("( {0} IS NULL )", parameter.MemberName);
-        //}
+    { 
         public override string WeekOfYear(MethodCallExpressionModel mode)
         {
             var parameterNameA = mode.Args[0].MemberName;