Issue #48 implemented switch function

EPPlusSoftware · Feb 28, 2020 · fbf4d6d · fbf4d6d
1 parent ec86904
commit fbf4d6d
Show file tree

Hide file tree

Showing 4 changed files with 112 additions and 1 deletion.
diff --git a/src/EPPlus/FormulaParsing/Excel/Functions/BuiltInFunctions.cs b/src/EPPlus/FormulaParsing/Excel/Functions/BuiltInFunctions.cs
@@ -151,6 +151,7 @@ public BuiltInFunctions()
             Functions["or"] = new Or();
             Functions["true"] = new True();
             Functions["false"] = new False();
+            Functions["switch"] = new Switch();
             // Reference and lookup
             Functions["address"] = new Address();
             Functions["hlookup"] = new HLookup();

diff --git a/src/EPPlus/FormulaParsing/Excel/Functions/Logical/Ifs.cs b/src/EPPlus/FormulaParsing/Excel/Functions/Logical/Ifs.cs
@@ -6,7 +6,7 @@
 
 namespace OfficeOpenXml.FormulaParsing.Excel.Functions.Logical
 {
-    public class Ifs : ExcelFunction
+    internal class Ifs : ExcelFunction
     {
         public override CompileResult Execute(IEnumerable<FunctionArgument> arguments, ParsingContext context)
         {

diff --git a/src/EPPlus/FormulaParsing/Excel/Functions/Logical/Switch.cs b/src/EPPlus/FormulaParsing/Excel/Functions/Logical/Switch.cs
@@ -0,0 +1,69 @@
+using OfficeOpenXml.FormulaParsing.ExpressionGraph;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+
+namespace OfficeOpenXml.FormulaParsing.Excel.Functions.Logical
+{
+    internal class Switch : ExcelFunction
+    {
+        public Switch()
+            : this(new CompileResultFactory())
+        {
+
+        }
+        public Switch(CompileResultFactory compileResultFactory)
+        {
+            _compileResultFactory = compileResultFactory;
+        }
+
+        private readonly CompileResultFactory _compileResultFactory;
+
+        public override CompileResult Execute(IEnumerable<FunctionArgument> arguments, ParsingContext context)
+        {
+            ValidateArguments(arguments, 3);
+            var expression = arguments.ElementAt(0).ValueFirst;
+            var maxLength = 1 + 126 * 2;
+            for(var x = 1; x < (arguments.Count() - 1) || x >= maxLength; x += 2)
+            {
+                var candidate = arguments.ElementAt(x).Value;
+                if(IsMatch(expression, candidate))
+                {
+                    return _compileResultFactory.Create(arguments.ElementAt(x + 1).Value);
+                }
+            }
+            if (arguments.Count() % 2 == 0) return _compileResultFactory.Create(arguments.Last().Value);
+            return new CompileResult(eErrorType.NA);
+        }
+
+        private bool IsMatch(object right, object left)
+        {
+            if(IsNumeric(right) || IsNumeric(left))
+            {
+                var r = GetNumericValue(right);
+                var l = GetNumericValue(left);
+                return r.Equals(l);
+            }
+            if(right == null && left == null)
+            {
+                return true;
+            }
+            if (right == null) return false;
+            return right.Equals(left);
+        }
+
+        private double GetNumericValue(object obj)
+        {
+            if(obj is System.DateTime)
+            {
+                return ((System.DateTime)obj).ToOADate();
+            }
+            if(obj is TimeSpan)
+            {
+                return ((TimeSpan)obj).TotalMilliseconds;
+            }
+            return Convert.ToDouble(obj);
+        }
+    }
+}
diff --git a/src/EPPlusTest/FormulaParsing/Excel/Functions/LogicalFunctionsTests.cs b/src/EPPlusTest/FormulaParsing/Excel/Functions/LogicalFunctionsTests.cs
@@ -259,5 +259,46 @@ public void IfNaShouldReturnResultOfFormulaIfNoError()
                 Assert.AreEqual("hi there", s1.Cells["A1"].Value);
             }
         }
+
+        [TestMethod]
+        public void SwitchShouldReturnFirstMatchingArg()
+        {
+            using (var package = new ExcelPackage())
+            {
+                var s1 = package.Workbook.Worksheets.Add("test");
+                s1.Cells["A1"].Formula = "SWITCH(A2, 1, 2)";
+                s1.Cells["A2"].Value = 1;
+                s1.Calculate();
+                Assert.AreEqual(2d, s1.Cells["A1"].Value);
+            }
+        }
+
+        [TestMethod]
+        public void SwitchShouldIgnoreNonMatchingArg()
+        {
+            using (var package = new ExcelPackage())
+            {
+                var s1 = package.Workbook.Worksheets.Add("test");
+                s1.Cells["A1"].Formula = "SWITCH(A2, 1, 2, B2, 3)";
+                s1.Cells["A2"].Value = 2;
+                s1.Cells["B2"].Value = 2d;
+                s1.Calculate();
+                Assert.AreEqual(3d, s1.Cells["A1"].Value);
+            }
+        }
+
+        [TestMethod]
+        public void SwitchShouldReturnLastArgIfNoMatch()
+        {
+            using (var package = new ExcelPackage())
+            {
+                var s1 = package.Workbook.Worksheets.Add("test");
+                s1.Cells["A1"].Formula = "SWITCH(A2, 1, 2, B2, 3, 5)";
+                s1.Cells["A2"].Value = -1;
+                s1.Cells["B2"].Value = 2d;
+                s1.Calculate();
+                Assert.AreEqual(5d, s1.Cells["A1"].Value);
+            }
+        }
     }
 }