#33 - DateSerial parser.

Author: techyian

src/ReportViewer.NET/Parsers/DateAndTime/DateSerialParser.cs

@@ -0,0 +1,84 @@
+using ReportViewer.NET.DataObjects;
+using ReportViewer.NET.Extensions;
+using System.Collections.Generic;
+using System.Text.RegularExpressions;
+using System;
+
+namespace ReportViewer.NET.Parsers.DateAndTime
+{
+    public class DateSerialParser : BaseParser
+    {
+        public static Regex DateSerialRegex = RegexCommon.GenerateMultiParamParserRegex("DateSerial");
+
+        public DateSerialParser(
+            string currentString,
+            ExpressionFieldOperator op,
+            ReportExpression currentExpression,
+            IEnumerable<IDictionary<string, object>> dataSetResults,
+            IDictionary<string, object> values,
+            int currentRowNumber,
+            IEnumerable<DataSet> dataSets,
+            DataSet activeDataset,
+            ReportRDL report
+        ) : base(currentString, op, currentExpression, dataSetResults, values, currentRowNumber, dataSets, activeDataset, DateSerialRegex, report)
+        {
+        }
+
+        public override (Type, object) ExtractExpressionValue(string fieldName, string dataSetName)
+        {
+            throw new NotImplementedException();
+        }
+
+        public override void Parse()
+        {
+            var match = DateSerialRegex.Match(CurrentString);
+            var matchValue = match.Value;
+
+            // Remove the surrounding DateSerial including open & close brace so we can inspect inner members and see if they too contain program flow expressions. 
+            matchValue = matchValue.MatchValueSubString(11);
+
+            var foundParameters = this.ParseParenthesis(matchValue);
+
+            if (foundParameters.Item2.Count != 3)
+            {
+                // The DateSerial function expects 3 parameters.
+                return;
+            }
+
+            // DateTime will either come directly from database or will be calculated from other expression.
+            var year = this.Report.Parser.ParseReportExpressionString(
+                foundParameters.Item2[0],
+                this.DataSetResults,
+                this.Values,
+                this.CurrentRowNumber,
+                this.DataSets,
+                this.ActiveDataset,
+                null
+            ).ExpressionAsInt();
+
+            var month = this.Report.Parser.ParseReportExpressionString(
+                foundParameters.Item2[1],
+                this.DataSetResults,
+                this.Values,
+                this.CurrentRowNumber,
+                this.DataSets,
+                this.ActiveDataset,
+                null
+            ).ExpressionAsInt();
+
+            var day = this.Report.Parser.ParseReportExpressionString(
+                foundParameters.Item2[2],
+                this.DataSetResults,
+                this.Values,
+                this.CurrentRowNumber,
+                this.DataSets,
+                this.ActiveDataset,
+                null
+            ).ExpressionAsInt();
+
+            this.CurrentExpression.Index = match.Index;
+            this.CurrentExpression.ResolvedType = typeof(DateTime);
+            this.CurrentExpression.Value = new DateTime(year, month, day, 0, 0, 0);
+        }
+    }
+}

src/ReportViewer.NET/Parsers/ExpressionFieldOperator.cs

@@ -56,6 +56,7 @@ public enum ExpressionFieldOperator
         DateAdd,
         DateDiff,
         DatePart,
+        DateSerial,
         Day,
         Now,
         DateValue,

src/ReportViewer.NET/Parsers/ExpressionParser.cs

@@ -515,6 +515,15 @@ ref string proposedString
                 proposedString = datePartParser.GetProposedString();
             }
 
+            if (DateSerialParser.DateSerialRegex.IsMatch(currentString) &&
+                (currentExpression.Operator == ExpressionFieldOperator.None || DateSerialParser.DateSerialRegex.Match(currentString).Index < currentExpression.Index)
+            )
+            {
+                var dateSerialParser = new DateSerialParser(currentString, ExpressionFieldOperator.DateSerial, currentExpression, dataSetResults, values, currentRowNumber, dataSets, activeDataset, _report);
+                dateSerialParser.Parse();
+                proposedString = dateSerialParser.GetProposedString();
+            }
+
             if (DayParser.DayRegex.IsMatch(currentString) &&
                 ((WeekdayParser.WeekdayRegex.IsMatch(currentString) && DayParser.DayRegex.Match(currentString).Index < WeekdayParser.WeekdayRegex.Match(currentString).Index) || !WeekdayParser.WeekdayRegex.IsMatch(currentString)) &&
                 (currentExpression.Operator == ExpressionFieldOperator.None || DayParser.DayRegex.Match(currentString).Index < currentExpression.Index)

test/ReportViewer.NET.Tests/Parsers/DateAndTime/DateSerialParserTests.cs

@@ -0,0 +1,72 @@
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+using ReportViewer.NET.DataObjects;
+using ReportViewer.NET.Extensions;
+using ReportViewer.NET.Parsers;
+using System.Globalization;
+
+namespace ReportViewer.NET.Tests.Parsers.DateAndTime
+{
+    [TestClass]
+    public class DateSerialParserTests
+    {
+        private ExpressionParser _expressionParser;
+        private ReportRDL _report;
+
+        public DateSerialParserTests()
+        {
+            var report = TestHelper.PrimeReport();
+
+            _report = report;
+            _expressionParser = new ExpressionParser(report);
+        }
+
+        [TestMethod]
+        public void DateSerial_Returns_DateTime()
+        {
+            // Arrange
+            var expr = "=DateSerial(DatePart(\"yyyy\",\"January 15, 2010 14:30:15\")-10, DatePart(\"m\",\"January 15, 2010 14:30:15\")+3,DatePart(\"d\",\"January 15, 2010 14:30:15\")-1)";
+            
+            // Act
+            var result = _expressionParser.ParseReportExpressionString(
+                expr,
+                null,
+                null,
+                1,
+                _report.DataSets,
+                null,
+                null
+            ).ExpressionAsDateTime();
+
+            // Assert            
+            Assert.AreEqual(new DateTime(2000, 4, 14, 0, 0, 0), result);
+        }
+
+        [TestMethod]
+        public void DateSerial_Returns_String()
+        {
+            // Arrange
+            var expr = "=\"DateSerial parsed as \" & FormatDateTime(DateSerial(DatePart(\"yyyy\",\"January 15, 2010 14:30:15\")-10, DatePart(\"m\",\"January 15, 2010 14:30:15\")+3,DatePart(\"d\",\"January 15, 2010 14:30:15\")-1), DateFormat.ShortDate)";
+            var cultureInfo = new CultureInfo("en-GB");
+            CultureInfo originalCulture = Thread.CurrentThread.CurrentCulture;
+            CultureInfo.DefaultThreadCurrentCulture = cultureInfo;
+            CultureInfo.DefaultThreadCurrentUICulture = cultureInfo;
+
+            // Act
+            var result = _expressionParser.ParseReportExpressionString(
+                expr,
+                null,
+                null,
+                1,
+                _report.DataSets,
+                null,
+                null
+            ).ExpressionAsString();
+
+            // Assert            
+            Assert.AreEqual("DateSerial parsed as 14/04/2000", result);
+
+            CultureInfo.DefaultThreadCurrentCulture = originalCulture;
+            CultureInfo.DefaultThreadCurrentUICulture = originalCulture;
+        }
+    }
+}