diff --git a/SqlSugar/ExpressionsToSql/Method/SqlFunc.cs b/SqlSugar/ExpressionsToSql/Method/SqlFunc.cs
index 1b1d8d290..653a20412 100644
--- a/SqlSugar/ExpressionsToSql/Method/SqlFunc.cs
+++ b/SqlSugar/ExpressionsToSql/Method/SqlFunc.cs
@@ -16,13 +16,34 @@ namespace SqlSugar
         {
             return thisValue.IsValuable();
         }
-        public static bool IsNullOrEmpty(object thisValue) { throw new NotImplementedException(); }
-        public static string ToLower(object thisValue) { throw new NotImplementedException(); }
-        public static string ToUpper(object thisValue) { throw new NotImplementedException(); }
-        public static string Trim(object thisValue) { throw new NotImplementedException(); }
-        public static bool Contains(string thisValue, string parameterValue) { throw new NotImplementedException(); }
-        public static bool ContainsArray<T>(T[] thisValue, object parameterValue) { throw new NotImplementedException(); }
-        public static bool StartsWith(object thisValue, string parameterValue) { throw new NotImplementedException(); }
+        public static bool IsNullOrEmpty(object thisValue)
+        {
+            return thisValue.IsNullOrEmpty();
+        }
+        public static string ToLower(object thisValue)
+        {
+            return thisValue == null ? null : thisValue.ToString().ToLower();
+        }
+        public static string ToUpper(object thisValue)
+        {
+            return thisValue == null ? null : thisValue.ToString().ToUpper();
+        }
+        public static string Trim(object thisValue)
+        {
+            return thisValue == null ? null : thisValue.ToString().Trim();
+        }
+        public static bool Contains(string thisValue, string parameterValue)
+        {
+            return thisValue.Contains(parameterValue);
+        }
+        public static bool ContainsArray<T>(T[] thisValue, object parameterValue)
+        {
+            return thisValue.Contains((T)parameterValue);
+        }
+        public static bool StartsWith(string thisValue, string parameterValue)
+        {
+            return thisValue.StartsWith(parameterValue);
+        }
         public static bool EndsWith(object thisValue, string parameterValue) { throw new NotImplementedException(); }
         public new static bool Equals(object thisValue, object parameterValue) { throw new NotImplementedException(); }
         public static bool DateIsSame(DateTime date1, DateTime date2) { throw new NotImplementedException(); }