Add IQuantity.Value (#612)

* Add IQuantity.Value

Value type double as is the standard contract for conversion property getters,
until we add support for different value types.

Author: angularsen

UnitsNet/GeneratedCode/Quantities/BitRate.NetFramework.g.cs

@@ -28,7 +28,7 @@ namespace UnitsNet
     /// <summary>
     ///     Represents a quantity.
     /// </summary>
-    public partial interface IQuantity
+    public interface IQuantity
     {
         /// <summary>
         ///     The <see cref="QuantityType" /> of this quantity.
@@ -58,6 +58,11 @@ public partial interface IQuantity
         /// </summary>
         Enum Unit { get; }
 
+        /// <summary>
+        ///     The value this quantity was constructed with. Should be seen in combination with <see cref="Unit"/>.
+        /// </summary>
+        double Value { get; }
+
         /// <summary>
         ///     Change the default unit representation of the quantity, which affects things like <see cref="IQuantity.ToString(System.IFormatProvider)"/>.
         /// </summary>

UnitsNet/GeneratedCode/Quantities/Information.NetFramework.g.cs

@@ -348,8 +348,8 @@ function GenerateProperties([GeneratorArgs]$genArgs)
 {
   $quantityName = $genArgs.Quantity.Name
   $unitEnumName = $genArgs.UnitEnumName
-  $baseUnitSingularName = $genArgs.BaseUnit.SingularName
   $valueType = $genArgs.Quantity.BaseType
+  [bool]$isDoubleValueType = $valueType -eq "double"
 @"
 
         #region Properties
@@ -359,6 +359,10 @@ function GenerateProperties([GeneratorArgs]$genArgs)
         /// </summary>
         public $valueType Value => _value;
 
+"@; if (-not $isDoubleValueType) { @"
+        double IQuantity.Value => (double) _value;
+
+"@; } @"
         /// <inheritdoc cref="IQuantity.Unit"/>
         Enum IQuantity.Unit => Unit;