diff --git a/Src/Asp.NetCore2/SqlSugar/ExpressionsToSql/ResolveItems/BaseResolve_Item.cs b/Src/Asp.NetCore2/SqlSugar/ExpressionsToSql/ResolveItems/BaseResolve_Item.cs
index 9d7e7fcc1..27fd2052d 100644
--- a/Src/Asp.NetCore2/SqlSugar/ExpressionsToSql/ResolveItems/BaseResolve_Item.cs
+++ b/Src/Asp.NetCore2/SqlSugar/ExpressionsToSql/ResolveItems/BaseResolve_Item.cs
@@ -21,7 +21,8 @@ namespace SqlSugar
             else if (ExpressionTool.GetMethodName(item) == "ToString"   
                                       &&(item as MethodCallExpression)?.Arguments?.Count()==1
                                       && (item as MethodCallExpression)?.Object?.Type!=UtilConstants.DateType
-                                      && this.Context?.SugarContext?.QueryBuilder!=null)
+                                      && this.Context?.SugarContext?.QueryBuilder!=null
+                                      && !ExpressionTool.GetParameters((item as MethodCallExpression)?.Arguments.First()).Any())
             {
                 var format=ExpressionTool.GetExpressionValue((item as MethodCallExpression)?.Arguments[0]);
                 var childExpression = (item as MethodCallExpression)?.Object;