Add Sunfunc.EqualsNull

Src/Asp.Net/SqlServerTest/Demo/Demo1_Queryable.cs

@@ -30,7 +30,7 @@ namespace OrmTest
             Console.WriteLine("#### Examples Start ####");
             var db = GetInstance();
             var dbTime = db.GetDate();
-            var getAll = db.Queryable<Order>().ToList();
+            var getAll = db.Queryable<Order>().Where(it=> SqlFunc.EqualsNull(it.Name,null)).ToList();
             var getOrderBy = db.Queryable<Order>().OrderBy(it => it.Name,OrderByType.Desc).ToList();
             var getOrderBy2 = db.Queryable<Order>().OrderBy(it => it.Id).OrderBy(it => it.Name, OrderByType.Desc).ToList();
             var getOrderBy3 = db.Queryable<Order>().OrderBy(it =>new { it.Name,it.Id}).ToList();

Src/Asp.Net/SqlSugar/ExpressionsToSql/DbMethods/DefaultDbMethod.cs

@@ -138,6 +138,19 @@ namespace SqlSugar
             return string.Format(" ({0} = {1}) ", parameter.MemberName, parameter2.MemberName); ;
         }
 
+        public virtual string EqualsNull(MethodCallExpressionModel model)
+        {
+            var parameter = model.Args[0];
+            var parameter2 = model.Args[1];
+            if (parameter2.MemberValue == null)
+            {
+                return string.Format(" ({0} is null) ", parameter.MemberName, parameter2.MemberName) ;
+            }
+            else
+            {
+                return string.Format(" ({0} = {1}) ", parameter.MemberName, parameter2.MemberName);
+            }
+        }
         public virtual string DateIsSameDay(MethodCallExpressionModel model)
         {
             var parameter = model.Args[0];

Src/Asp.Net/SqlSugar/ExpressionsToSql/DbMethods/IDbMethods.cs

@@ -22,6 +22,7 @@ namespace SqlSugar
         string ContainsArray(MethodCallExpressionModel model);
         string ContainsArrayUseSqlParameters(MethodCallExpressionModel model);
         string Equals(MethodCallExpressionModel model);
+        string EqualsNull(MethodCallExpressionModel model);
         string DateIsSameDay(MethodCallExpressionModel model);
         string DateIsSameByType(MethodCallExpressionModel model);
         string DateAddByType(MethodCallExpressionModel model);

Src/Asp.Net/SqlSugar/ExpressionsToSql/DbMethods/SqlFunc.cs

@@ -65,6 +65,10 @@ namespace SqlSugar
         {
             return thisValue.Equals(parameterValue);
         }
+        public new static bool EqualsNull(object thisValue, object parameterValue)
+        {
+            return thisValue.Equals(parameterValue);
+        }
         public static bool DateIsSame(DateTime date1, DateTime date2)
         {
             return date1.ToString("yyyy-MM-dd") == date2.ToString("yyyy-MM-dd");

Src/Asp.Net/SqlSugar/ExpressionsToSql/ResolveItems/MethodCallExpressionResolve.cs

@@ -568,6 +568,8 @@ namespace SqlSugar
                         return caResult2;
                     case "Equals":
                         return this.Context.DbMehtods.Equals(model);
+                    case "EqualsNull":
+                        return this.Context.DbMehtods.EqualsNull(model);
                     case "DateIsSame":
                         if (model.Args.Count == 2)
                             return this.Context.DbMehtods.DateIsSameDay(model);