Managed API: Refactoring and formatting.

Signed-off-by: Christoph M. Wintersteiger <cwinter@microsoft.com>

src/api/dotnet/RatNum.cs

@@ -0,0 +1,111 @@
+/*++
+Copyright (c) 2012 Microsoft Corporation
+
+Module Name:
+
+    IntNum.cs
+
+Abstract:
+
+    Z3 Managed API: Int Numerals
+
+Author:
+
+    Christoph Wintersteiger (cwinter) 2012-03-20
+
+Notes:
+    
+--*/
+using System;
+using System.Diagnostics.Contracts;
+
+#if !FRAMEWORK_LT_4
+using System.Numerics;
+#endif
+
+namespace Microsoft.Z3
+{
+    /// <summary>
+    /// Rational Numerals
+    /// </summary>
+    [ContractVerification(true)]
+    public class RatNum : RealExpr
+    {
+        /// <summary>
+        /// The numerator of a rational numeral.
+        /// </summary>
+        public IntNum Numerator
+        {
+            get
+            {
+                Contract.Ensures(Contract.Result<IntNum>() != null);
+
+                return new IntNum(Context, Native.Z3_get_numerator(Context.nCtx, NativeObject));
+            }
+        }
+
+        /// <summary>
+        /// The denominator of a rational numeral.
+        /// </summary>
+        public IntNum Denominator
+        {
+            get
+            {
+                Contract.Ensures(Contract.Result<IntNum>() != null);
+
+                return new IntNum(Context, Native.Z3_get_denominator(Context.nCtx, NativeObject));
+            }
+        }
+
+#if !FRAMEWORK_LT_4
+        /// <summary>
+        /// Converts the numerator of the rational to a BigInteger
+        /// </summary>
+        public BigInteger BigIntNumerator
+        {
+            get
+            {
+                IntNum n = Numerator;
+                return BigInteger.Parse(n.ToString());
+            }
+        }
+
+        /// <summary>
+        /// Converts the denominator of the rational to a BigInteger
+        /// </summary>
+        public BigInteger BigIntDenominator
+        {
+            get
+            {
+                IntNum n = Denominator;
+                return BigInteger.Parse(n.ToString());
+            }
+        }
+#endif
+
+        /// <summary>
+        /// Returns a string representation in decimal notation.
+        /// </summary>
+        /// <remarks>The result has at most <paramref name="precision"/> decimal places.</remarks>    
+        public string ToDecimalString(uint precision)
+        {
+            return Native.Z3_get_numeral_decimal_string(Context.nCtx, NativeObject, precision);
+        }
+
+        /// <summary>
+        /// Returns a string representation of the numeral.
+        /// </summary>        
+        public override string ToString()
+        {
+            return Native.Z3_get_numeral_string(Context.nCtx, NativeObject);
+        }
+
+        #region Internal
+        internal RatNum(Context ctx, IntPtr obj)
+            : base(ctx, obj)
+        {
+            Contract.Requires(ctx != null);
+        }
+        #endregion
+    }
+}