Add ToString() overloads so it's easier to format values for different cultures.

Author: RobThree

DSMRParser.Tests/TelegramTests.cs

@@ -0,0 +1,35 @@
+using DSMRParser.Models;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+using System.Globalization;
+using System.Linq;
+
+namespace DSMRParser.Tests;
+
+[TestClass]
+public class TelegramTests
+{
+    [TestMethod]
+    public void ToString_Should_FormatCorrectly()
+    {
+        var telegram = new Telegram("foo", [
+            (OBISRegistry.VoltageL1.Id, ["1234.56*V"]),
+            (OBISRegistry.GasDelivered.Id, ["201211100907S", "6789.12*m3"]),
+            (OBISRegistry.ElectricityFailures.Id, ["42"]),
+            (OBISRegistry.ElectricityFailureLog.Id, ["000104180320W","0000237126*s","000101000001W","2147583646*s","200102010203W","2317482647*s"]),
+        ]);
+
+        Assert.AreEqual("1234.56V", telegram.VoltageL1!.ToString());
+        Assert.AreEqual("2020-12-11T10:09:07.0000000+01:00: 6789.12m³", telegram.GasDelivered!.ToString());
+        Assert.AreEqual("2000-01-01T00:00:01.0000000+01:00: 24856.07:00:46", telegram.ElectricityFailureLog.ToArray()[0].ToString());
+
+        var nl_culture = CultureInfo.GetCultureInfo(1043);
+        Assert.AreEqual("1234,56V", telegram.VoltageL1!.ToString(nl_culture));
+        Assert.AreEqual("2020-12-11T10:09:07.0000000+01:00: 6789,12m³", telegram.GasDelivered!.ToString(nl_culture));
+        Assert.AreEqual("11-12-20 10:09:07: 6789,12m³", telegram.GasDelivered!.ToString(null, "dd-MM-yy HH:mm:ss", nl_culture));
+
+        var us_culture = CultureInfo.GetCultureInfo(1033);
+        Assert.AreEqual("1234.56V", telegram.VoltageL1!.ToString(us_culture));
+        Assert.AreEqual("2020-12-11T10:09:07.0000000+01:00: 6789.12m³", telegram.GasDelivered!.ToString(us_culture));
+        Assert.AreEqual("12/11/20 10:09:07: 6789.12m³", telegram.GasDelivered!.ToString(null, "MM/dd/yy HH:mm:ss", us_culture));
+    }
+}

DSMRParser/Models/IUnitValue.cs

@@ -0,0 +1,8 @@
+using System;
+
+namespace DSMRParser.Models;
+
+internal interface IUnitValue
+{
+    string ToString(string? format, IFormatProvider? provider);
+}

DSMRParser/Models/OBISUnit.cs

@@ -5,7 +5,7 @@
 /// </summary>
 public enum OBISUnit
 {
-    /// <summary>Unit-less</summary>
+    /// <summary>Unitless</summary>
     NONE,
     /// <summary>Watts</summary>
     W,

DSMRParser/Models/OBISUnitExtensions.cs

@@ -0,0 +1,21 @@
+namespace DSMRParser.Models;
+
+/// <summary>
+/// Extension methods for <see cref="OBISUnit"/>.
+/// </summary>
+public static class OBISUnitExtensions
+{
+    /// <summary>
+    /// Converts the <see cref="OBISUnit"/> to a string.
+    /// </summary>
+    /// <param name="unit">The <see cref="OBISUnit"/> to convert.</param>
+    /// <returns>Returns a string representing the <see cref="OBISUnit"/>.</returns>
+    public static string ToUnitString(this OBISUnit unit)
+        => unit switch
+        {
+            OBISUnit.NONE => string.Empty,
+            OBISUnit.m3 => "m³",
+            OBISUnit.dm3 => "dm³",
+            _ => unit.ToString()
+        };
+}

DSMRParser/Models/Telegram.cs

@@ -63,7 +63,9 @@ public class Telegram(string? identification, IEnumerable<(OBISId obisid, IEnume
     /// <summary>Number of long power failures in any phase.</summary>
     public int? ElectricityLongFailures => ParseInt(OBISRegistry.ElectricityLongFailures);
     /// <summary>Power Failure Event Log.</summary>
-    public IEnumerable<TimeStampedValue<TimeSpan>> ElectricityFailureLog => ParseTimeStampedValues(OBISRegistry.ElectricityFailureLog, (d, v) => TimeSpan.FromSeconds(ParseLongUnit(d, v)?.Value ?? 0), 2);
+    public IEnumerable<TimeStampedValue<TimeSpan>> ElectricityFailureLog
+        => ParseTimeStampedValues(OBISRegistry.ElectricityFailureLog, (d, v) => TimeSpan.FromSeconds(ParseLongUnit(d, v)?.Value ?? 0), 2);
+
     /// <summary>Number of voltage sags in phase L1.</summary>
     public int? ElectricitySagsL1 => ParseInt(OBISRegistry.ElectricitySagsL1);
     /// <summary>Number of voltage sags in phase L2.</summary>
@@ -213,7 +215,8 @@ protected static bool TryParseDateTimeOffsetCore(string? value, out DateTimeOffs
     /// <paramref name="result"/> contains a valid <see cref="byte"/> or null when the method returns false.
     /// </param>
     /// <returns>True if the parse operation was successful; otherwise, false.</returns>
-    protected static bool TryParseHexByteCore(string? value, out byte result) => byte.TryParse(value, NumberStyles.HexNumber, _culture, out result);
+    protected static bool TryParseHexByteCore(string? value, out byte result)
+        => byte.TryParse(value, NumberStyles.HexNumber, _culture, out result);
 
     /// <summary>
     /// Attempts to parse an integer value.
@@ -224,7 +227,8 @@ protected static bool TryParseDateTimeOffsetCore(string? value, out DateTimeOffs
     /// <paramref name="result"/> contains a valid <see cref="int"/> or null when the method returns false.
     /// </param>
     /// <returns>True if the parse operation was successful; otherwise, false.</returns>
-    protected static bool TryParseIntCore(string? value, out int result) => int.TryParse(value, NumberStyles.Integer, _culture, out result);
+    protected static bool TryParseIntCore(string? value, out int result)
+        => int.TryParse(value, NumberStyles.Integer, _culture, out result);
 
     /// <summary>
     /// Attempts to parse a long value.
@@ -235,7 +239,8 @@ protected static bool TryParseDateTimeOffsetCore(string? value, out DateTimeOffs
     /// <paramref name="result"/> contains a valid <see cref="long"/> or null when the method returns false.
     /// </param>
     /// <returns>True if the parse operation was successful; otherwise, false.</returns>
-    protected static bool TryParseLongCore(string? value, out long result) => long.TryParse(value, NumberStyles.Integer, _culture, out result);
+    protected static bool TryParseLongCore(string? value, out long result)
+        => long.TryParse(value, NumberStyles.Integer, _culture, out result);
 
     /// <summary>
     /// Attempts to parse a decimal value.
@@ -246,7 +251,8 @@ protected static bool TryParseDateTimeOffsetCore(string? value, out DateTimeOffs
     /// <paramref name="result"/> contains a valid <see cref="decimal"/> or null when the method returns false.
     /// </param>
     /// <returns>True if the parse operation was successful; otherwise, false.</returns>
-    protected static bool TryParseDecimalCore(string? value, out decimal result) => decimal.TryParse(value, NumberStyles.AllowDecimalPoint, _culture, out result);
+    protected static bool TryParseDecimalCore(string? value, out decimal result)
+        => decimal.TryParse(value, NumberStyles.AllowDecimalPoint, _culture, out result);
 
     /// <summary>
     /// Attempts to parse an enum value.
@@ -258,7 +264,8 @@ protected static bool TryParseDateTimeOffsetCore(string? value, out DateTimeOffs
     /// <paramref name="result"/> contains a valid enum value or null when the method returns false.
     /// </param>
     /// <returns>True if the parse operation was successful; otherwise, false.</returns>
-    protected static bool TryParseEnumCore<T>(string? value, out T result) where T : struct => Enum.TryParse<T>(value, out result);
+    protected static bool TryParseEnumCore<T>(string? value, out T result)
+        where T : struct => Enum.TryParse<T>(value, out result);
 
     /// <summary>
     /// Parses a timestamp in yyMMddHHmmss to a <see cref="DateTimeOffset"/>.
@@ -329,7 +336,8 @@ protected static bool TryParseDateTimeOffsetCore(string? value, out DateTimeOffs
     /// The <see cref="OBISDescriptor"/> specifying the value to find in the telegram and parse as <see cref="UnitValue{T}"/>
     /// </param>
     /// <returns>Returns a <see cref="UnitValue{T}"/> when parsing the given <paramref name="descriptor"/> succeeded, null otherwise.</returns>
-    protected UnitValue<int>? ParseIntUnit(OBISDescriptor descriptor) => ParseIntUnit(descriptor, GetByDescriptor(descriptor));
+    protected UnitValue<int>? ParseIntUnit(OBISDescriptor descriptor)
+        => ParseIntUnit(descriptor, GetByDescriptor(descriptor));
     /// <summary>
     /// Attempts to parse a given value with unit from a given <see cref="OBISDescriptor"/>.
     /// </summary>
@@ -406,7 +414,8 @@ protected static bool TryParseDateTimeOffsetCore(string? value, out DateTimeOffs
     /// <param name="expected">The expected <see cref="OBISUnit"/> the value should represent.</param>
     /// <param name="actual">The actual unit the value represents.</param>
     /// <returns>True when the given string matches the given <see cref="OBISUnit"/>, false otherwise.</returns>
-    protected static bool IsCorrectUnit(OBISUnit expected, string? actual) => TryParseEnumCore<OBISUnit>(actual, out var result) && expected == result;
+    protected static bool IsCorrectUnit(OBISUnit expected, string? actual)
+        => TryParseEnumCore<OBISUnit>(actual, out var result) && expected == result;
 
     /// <summary>
     /// Parses values in (date)(value)(date)(value)... format to an <see cref="TimeStampedValue{T}"/> enumerable.
@@ -462,7 +471,9 @@ protected static (string? value, string? unit) SplitValues(string? value, char u
     /// </summary>
     /// <param name="value">The "hex byte format string".</param>
     /// <returns>The string the "hex byte string" represents.</returns>
-    protected static string? DecodeString(string? value) => (!string.IsNullOrEmpty(value) && value.Length % 2 == 0) ? Encoding.ASCII.GetString([.. DecodeHexString(value)]) : value;
+    protected static string? DecodeString(string? value)
+        => (!string.IsNullOrEmpty(value) && value.Length % 2 == 0) ? Encoding.ASCII.GetString([.. DecodeHexString(value)]) : value;
+
     /// <summary>
     /// Decodes a string in "hex byte format" to it's byte values.
     /// </summary>

DSMRParser/Models/TimeStampedValue.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Globalization;
 
 namespace DSMRParser.Models;
 
@@ -32,5 +33,65 @@ public TimeStampedValue(DateTimeOffset? dateTimeOffset, T? value)
     /// Converts a <see cref="TimeStampedValue{T}"/> to a string.
     /// </summary>
     /// <returns>Returns a string representing a <see cref="TimeStampedValue{T}"/>.</returns>
-    public override string ToString() => $"{DateTime:O}: {Value}";
+    public override string ToString()
+        => ToString(null, null, null);
+
+    /// <summary>
+    /// Converts a <see cref="TimeStampedValue{T}"/> to a string.
+    /// </summary>
+    /// <param name="valueFormat">The format to use when formatting the value -or- a null
+    /// reference to use the default format defined for the type of the <see cref="IFormattable"/>
+    /// implementation.</param>
+    /// <param name="formatProvider">The provider to use to format the value.</param>
+    /// <returns>Returns a string representing a <see cref="TimeStampedValue{T}"/>.</returns>
+    public string ToString(string? valueFormat, IFormatProvider? formatProvider)
+        => ToString(valueFormat, null, formatProvider);
+
+    /// <summary>
+    /// Converts a <see cref="TimeStampedValue{T}"/> to a string.
+    /// </summary>
+    /// <param name="formatProvider">The provider to use to format the value.</param>
+    /// <returns>Returns a string representing a <see cref="TimeStampedValue{T}"/>.</returns>
+    public string ToString(IFormatProvider? formatProvider)
+        => ToString(null, null, formatProvider);
+
+    /// <summary>
+    /// Converts a <see cref="TimeStampedValue{T}"/> to a string.
+    /// </summary>
+    /// <param name="valueFormat">The format to use when formatting the value -or- a null
+    /// reference to use the default format defined for the type of the <see cref="IFormattable"/>
+    /// implementation.</param>
+    /// <param name="dateFormat">The format to use when formatting the datetime -or- a null
+    /// reference to use the default format defined for the type of the <see cref="IFormattable"/>
+    /// implementation.</param>
+    /// <param name="formatProvider">The provider to use to format the value.</param>
+    /// <returns>Returns a string representing a <see cref="TimeStampedValue{T}"/>.</returns>
+    public string ToString(string? valueFormat, string? dateFormat, IFormatProvider? formatProvider)
+    {
+        var date = GetFormattedDate(dateFormat, formatProvider);
+        var value = GetFormattedValue(valueFormat, formatProvider);
+
+        return !string.IsNullOrEmpty(date) && !string.IsNullOrEmpty(value)
+            ? $"{date}: {value}"
+            : !string.IsNullOrEmpty(date)
+            ? date
+            : !string.IsNullOrEmpty(value)
+            ? value : string.Empty;
+    }
+
+    private string GetFormattedDate(string? dateFormat, IFormatProvider? formatProvider)
+        => DateTime switch
+        {
+            null => string.Empty,
+            IFormattable formattable => formattable.ToString(dateFormat ?? "O", formatProvider ?? CultureInfo.InvariantCulture)
+        };
+
+    private string GetFormattedValue(string? valueFormat, IFormatProvider? formatProvider)
+        => Value switch
+        {
+            null => string.Empty,
+            IUnitValue unitValue => unitValue.ToString(valueFormat, formatProvider),
+            IFormattable formattable => formattable.ToString(valueFormat, formatProvider ?? CultureInfo.InvariantCulture),
+            _ => Value.ToString() ?? string.Empty
+        };
 }

DSMRParser/Models/UnitValue.cs

@@ -1,10 +1,13 @@
-namespace DSMRParser.Models;
+using System;
+using System.Globalization;
+
+namespace DSMRParser.Models;
 
 /// <summary>
 /// Represents a value in a given unit.
 /// </summary>
 /// <typeparam name="T">The type of the value.</typeparam>
-public record UnitValue<T>
+public record UnitValue<T> : IUnitValue
 {
     /// <summary>
     /// Gets the value.
@@ -27,8 +30,41 @@ public UnitValue(T? value, OBISUnit unit)
     }
 
     /// <summary>
-    /// Converts a <see cref="TimeStampedValue{T}"/> to a string.
+    /// Converts a <see cref="UnitValue{T}"/> to a string.
+    /// </summary>
+    /// <returns>Returns a string representing a <see cref="UnitValue{T}"/>.</returns>
+    public override string ToString()
+        => ToString(null, null);
+
+    /// <summary>
+    /// Converts a <see cref="UnitValue{T}"/> to a string.
+    /// </summary>
+    /// <param name="format">The format to use -or- a null reference to use the default format
+    /// defined for the type of the <see cref="IFormattable"/> implementation.</param>
+    /// <returns>Returns a string representing a <see cref="UnitValue{T}"/>.</returns>
+    public string ToString(string? format)
+        => ToString(format, null);
+
+    /// <summary>
+    /// Converts a <see cref="UnitValue{T}"/> to a string.
+    /// </summary>
+    /// <param name="formatProvider">The provider to use to format the value.</param>
+    /// <returns>Returns a string representing a <see cref="UnitValue{T}"/>.</returns>
+    public string ToString(IFormatProvider formatProvider)
+        => ToString(null, formatProvider);
+
+    /// <summary>
+    /// Converts a <see cref="UnitValue{T}"/> to a string.
     /// </summary>
-    /// <returns>Returns a string representing a <see cref="TimeStampedValue{T}"/>.</returns>
-    public override string ToString() => $"{Value}{Unit}";
-}
+    /// <param name="format">The format to use -or- a null reference to use the default format
+    /// defined for the type of the <see cref="IFormattable"/> implementation.</param>
+    /// <param name="formatProvider">The provider to use to format the value.</param>
+    /// <returns>Returns a string representing a <see cref="UnitValue{T}"/>.</returns>
+    public string ToString(string? format, IFormatProvider? formatProvider)
+        => Value switch
+        {
+            null => string.Empty,
+            IFormattable formattable => formattable.ToString(format, formatProvider ?? CultureInfo.InvariantCulture),
+            _ => Value.ToString() ?? string.Empty
+        } + Unit.ToUnitString();
+}