修改

Author: toolgood

csharp/ToolGood.Algorithm2.Test/AlgorithmEngine/AlgorithmEngineTest_flow.cs

@@ -36,7 +36,43 @@ public void iferror_test()
             t = engine.TryEvaluate("iferror(1-'rrr',1,2)", 0);
             Assert.AreEqual(1, t);
         }
- 
+
+        [Test]
+        public void iserror_test()
+        {
+            AlgorithmEngine engine = new AlgorithmEngine();
+            var t = engine.TryEvaluate("iserror(1/0,1)", 0);
+            Assert.AreEqual(1, t);
+
+            t = engine.TryEvaluate("iserror(1-'rrr',1)", 0);
+            Assert.AreEqual(1, t);
+        }
+        [Test]
+        public void ifnull_test()
+        {
+            AlgorithmEngine engine = new AlgorithmEngine();
+            var t = engine.TryEvaluate("isnull(null,1)", 0);
+            Assert.AreEqual(1, t);
+
+            t = engine.TryEvaluate("isnull(1,2)", 0);
+            Assert.AreEqual(1, t);
+        }
+
+        [Test]
+        public void isnullorerror_test()
+        {
+            AlgorithmEngine engine = new AlgorithmEngine();
+            var t = engine.TryEvaluate("isnullorerror(null,1)", 0);
+            Assert.AreEqual(1, t);
+
+            t = engine.TryEvaluate("isnullorerror(1/0,1)", 0);
+            Assert.AreEqual(1, t);
+
+            t = engine.TryEvaluate("isnullorerror(1,2)", 0);
+            Assert.AreEqual(1, t);
+        }
+
+
 
         [Test]
         public void ISNUMBER_test()
@@ -229,7 +265,7 @@ public void andor_Test()
 
         }
 
-  
+
 
 
     }

csharp/ToolGood.Algorithm2/AlgorithmEngine.cs

@@ -220,6 +220,9 @@ public string TryEvaluate(string exp, string def)
                 try
                 {
                     var obj = Evaluate();
+                    if (obj.IsNull) {
+                        return null;
+                    }
                     obj = obj.ToString("");
                     if (obj.IsError)
                     {

csharp/ToolGood.Algorithm2/Operand.cs

@@ -43,6 +43,9 @@ public static Operand Create(double obj)
         }
         public static Operand Create(string obj)
         {
+            if (object.Equals(null,obj)) {
+                return Operand.CreateNull();
+            }
             return new OperandString(obj);
         }
         public static Operand CreateJson(string txt)
@@ -202,7 +205,7 @@ public Operand ToArray(string errorMessage)
                             list.Add(Operand.Create(double.Parse(v.ToString(), NumberStyles.Any, cultureInfo)));
                         else if (v.IsLong)
                             list.Add(Operand.Create(double.Parse(v.ToString(), NumberStyles.Any, cultureInfo)));
-                        else if (v.IsLong)
+                        else if (v.IsNull)
                             list.Add(Operand.CreateNull());
                         else
                             list.Add(Operand.Create(v));
@@ -213,7 +216,6 @@ public Operand ToArray(string errorMessage)
             return Error(errorMessage);
         }
 
-
         public void Dispose() { }
     }
     public abstract class Operand<T> : Operand