1.1.12版本，支持常量pi、e、true、false

Author: toolgood

README.md

@@ -11,6 +11,7 @@ ToolGood.Algorithm֧
     }
     var c = engine.TryEvaluate("2+3", 0);
 ```
+支持常量`pi`,`e`,`true`,`false`
 
 ## 自定义参数
 ``` csharp

ToolGood.Algorithm.Test/AlgorithmEngine/AlgorithmEngineTest.cs

@@ -32,6 +32,16 @@ public void Test()
             b = engine.TryEvaluate("false", false);
             Assert.AreEqual(false, b);
 
+            var b1 = engine.TryEvaluate("if(true,1,2)", 0);
+            Assert.AreEqual(1, b1);
+
+            b1 = engine.TryEvaluate("if(false,1,2)", 0);
+            Assert.AreEqual(2, b1);
+
+            var b2 = engine.TryEvaluate("pi*4", 0.0);
+            Assert.AreEqual(Math.PI * 4, b2);
+            b2 = engine.TryEvaluate("e*4", 0.0);
+            Assert.AreEqual(Math.E * 4, b2);
         }
 
         [Test]

ToolGood.Algorithm/AlgorithmEngine.cs

@@ -92,7 +92,11 @@ public bool Parse(string exp)
                 }
                 #endregion
 
-                optType = Operator.ConvertOperator(curOpt);
+                optType = Operator.ConvertOperator(curOpt, texts[curPos]);
+                if (optType== OperatorType.PARAMETER) {
+                    operands.Push(new Operand(curOpt));
+                    continue;
+                }
                 funcCount = optType != OperatorType.FUNC ? 0 : getFunctionCount(texts, curPos);
 
                 //若运算符堆栈为空,或者若运算符堆栈栈顶为左括号,则将当前运算符直接存入运算符堆栈.

ToolGood.Algorithm/Properties/AssemblyInfo.cs

@@ -32,5 +32,5 @@
 //可以指定所有这些值，也可以使用“生成号”和“修订号”的默认值，
 // 方法是按如下所示使用“*”: :
 // [assembly: AssemblyVersion("1.0.*")]
-[assembly: AssemblyVersion("1.1.11.0")]
-[assembly: AssemblyFileVersion("1.1.11.0")]
+[assembly: AssemblyVersion("1.1.12.0")]
+[assembly: AssemblyFileVersion("1.1.12.0")]

ToolGood.Algorithm/_base/Operator.cs

@@ -8,15 +8,15 @@ namespace ToolGood.Algorithm
     /// <summary>
     /// 运算符
     /// </summary>
-    public class Operator
+    internal class Operator
     {
         public Operator(OperatorType type, string value)
         {
             this.Type = type;
             this.Value = value;
         }
 
-        public Operator(OperatorType type, string value,int argsCount)
+        public Operator(OperatorType type, string value, int argsCount)
         {
             this.Type = type;
             this.Value = value;
@@ -115,7 +115,7 @@ public Operator(OperatorType type, string value,int argsCount)
         /// </summary>
         /// <param name="opt">运算符</param>
         /// <returns>返回指定的运算符类型</returns>
-        public static OperatorType ConvertOperator(string opt)
+        public static OperatorType ConvertOperator(string opt, string next)
         {
             switch (opt) {
                 //case "!": return OperatorType.NOT;
@@ -135,8 +135,19 @@ public static OperatorType ConvertOperator(string opt)
                 case "&": return OperatorType.StringADD;
                 case "|": return OperatorType.OR;
                 case ",": return OperatorType.CA;
-                default: return OperatorType.FUNC;
+                default:break; // return OperatorType.FUNC;
             }
+            switch (opt) {
+                case "pi":
+                case "e":
+                case "true":
+                case "false":
+                    if (next == "(") {
+                        return OperatorType.FUNC;
+                    }
+                    return OperatorType.PARAMETER;
+            }
+            return OperatorType.FUNC;
         }
 
         /// <summary>

ToolGood.Algorithm/_base/OperatorType.cs

@@ -8,7 +8,7 @@ namespace ToolGood.Algorithm
     /// <summary>
     /// 运算符类型(从上到下优先级依次递减)，数值越大，优先级越低
     /// </summary>
-    public enum OperatorType
+    internal enum OperatorType
     {
         /// <summary>
         /// 左括号:(,left bracket
@@ -30,7 +30,10 @@ public enum OperatorType
         /// </summary>
         FUNC,
 
-
+        /// <summary>
+        /// 参数
+        /// </summary>
+        PARAMETER,
         ///// <summary>
         ///// 逻辑非,!,NOT
         ///// </summary>