diff --git a/mpir.net/mpir.net-tests/HugeFloatTests/ConstructionAndDisposal.cs b/mpir.net/mpir.net-tests/HugeFloatTests/ConstructionAndDisposal.cs
index 981da817..f539e961 100644
--- a/mpir.net/mpir.net-tests/HugeFloatTests/ConstructionAndDisposal.cs
+++ b/mpir.net/mpir.net-tests/HugeFloatTests/ConstructionAndDisposal.cs
@@ -127,6 +127,34 @@ namespace MPIR.Tests.HugeFloatTests
             }
         }
 
+        [TestMethod]
+        public void FloatStringConstructorWithAlternativeExponentMarker()
+        {
+            var n = "5432109876543212345789.70515331128527330659e3";
+            using(var a = new HugeFloat(n))
+            {
+                FloatAssert.AreEqual("5432109876543212345789705.15331128527330659", a);
+            }
+        }
+
+        [TestMethod]
+        public void FloatStringConstructorWithAlternativeExponentMarker2()
+        {
+            var n = "5432109876543212345789.70515331128527330659E3";
+            using(var a = new HugeFloat(n))
+            {
+                FloatAssert.AreEqual("5432109876543212345789705.15331128527330659", a);
+            }
+        }
+
+        [TestMethod]
+        [ExpectedException(typeof(ArgumentException))]
+        public void FloatStringConstructorWithAlternativeExponentMarkerInvalid()
+        {
+            var n = "5432109876543212345789.70515331128527330659e3";
+            var a = new HugeFloat(n, 11);
+        }
+
         [TestMethod]
         [ExpectedException(typeof(ArgumentException))]
         public void FloatStringConstructorInvalid()
@@ -144,6 +172,27 @@ namespace MPIR.Tests.HugeFloatTests
             }
         }
 
+        [TestMethod]
+        public void FloatStringConstructorHexExponentDecimal()
+        {
+            var n = "143210ABCDEF32123457ACDB324.59879@10";
+            using(var a = new HugeFloat(n, 16))
+            {
+                Assert.AreEqual("0.143210ABCDEF32123457ACDB32459879@37", a.ToString(16, false, true));
+            }
+        }
+
+        [TestMethod]
+        public void FloatStringConstructorHexExponentInBase()
+        {
+            var n = "143210ABCDEF32123457ACDB324.59879@10";
+            using(var a = new HugeFloat(n, 16, false))
+            {
+                Assert.AreEqual("0.143210ABCDEF32123457ACDB32459879@2B", a.ToString(16, false, false));
+                Assert.AreEqual("0.143210ABCDEF32123457ACDB32459879@43", a.ToString(16, false, true));
+            }
+        }
+
         [TestMethod]
         public void FloatConstructorFromExpression()
         {
diff --git a/mpir.net/mpir.net-tests/HugeFloatTests/Conversions.cs b/mpir.net/mpir.net-tests/HugeFloatTests/Conversions.cs
index 308afe8e..fdbd41a8 100644
--- a/mpir.net/mpir.net-tests/HugeFloatTests/Conversions.cs
+++ b/mpir.net/mpir.net-tests/HugeFloatTests/Conversions.cs
@@ -158,6 +158,23 @@ namespace MPIR.Tests.HugeFloatTests
             }
         }
 
+        [TestMethod]
+        public void FloatFromStringExpDecimal()
+        {
+            using(var a = new HugeFloat())
+            {
+                var n = "0.12354523094527035843ABCDEF54@10";
+                
+                a.SetTo(n, 16);
+                Assert.AreEqual("0.12354523094527035843ABCDEF54@10", a.ToString(16, false, true));
+                Assert.AreEqual("0.12354523094527035843ABCDEF54@A", a.ToString(16, false, false));
+
+                a.SetTo(n, 16, false);
+                Assert.AreEqual("0.12354523094527035843ABCDEF54@16", a.ToString(16, false, true));
+                Assert.AreEqual("0.12354523094527035843ABCDEF54@10", a.ToString(16, false, false));
+            }
+        }
+
         [TestMethod]
         [ExpectedException(typeof(ArgumentException))]
         public void FloatFromInvalidString()
diff --git a/mpir.net/mpir.net-tests/HugeFloatTests/IO.cs b/mpir.net/mpir.net-tests/HugeFloatTests/IO.cs
index f595ee82..c803a22a 100644
--- a/mpir.net/mpir.net-tests/HugeFloatTests/IO.cs
+++ b/mpir.net/mpir.net-tests/HugeFloatTests/IO.cs
@@ -45,7 +45,7 @@ namespace MPIR.Tests.HugeFloatTests
                 using (var reader = new StreamReader(ms, Encoding.UTF8, false, 1024, true))
                     b.Read(reader, 10, false);
 
-                Assert.AreEqual(a, b);
+                Assert.AreEqual(a.ToString(10), b.ToString(10));
                 Assert.AreEqual(ms.Length, ms.Position);
                 Assert.AreEqual((char)0xFEFF + a.ToString(10), Encoding.UTF8.GetString(ms.ToArray()));
             }
@@ -137,7 +137,7 @@ namespace MPIR.Tests.HugeFloatTests
                 using(var reader = new StreamReader(ms, Encoding.UTF8, false, 1024, true))
                     b.Read(reader, 62, false);
 
-                Assert.AreEqual(a, b);
+                Assert.AreEqual(a.ToString(62), b.ToString(62));
                 Assert.AreEqual(ms.Length, ms.Position);
                 Assert.AreEqual((char)0xFEFF + a.ToString(62), Encoding.UTF8.GetString(ms.ToArray()));
             }
diff --git a/mpir.net/mpir.net/HugeFloat.cpp b/mpir.net/mpir.net/HugeFloat.cpp
index 24a30cef..4fcb2828 100644
--- a/mpir.net/mpir.net/HugeFloat.cpp
+++ b/mpir.net/mpir.net/HugeFloat.cpp
@@ -71,14 +71,15 @@ namespace MPIR
         return result;
     }
 
-    void MPTYPE::FromString(String^ value, int base)
+    void MPTYPE::FromString(String^ value, int base, bool exponentInDecimal)
     {
         AllocateStruct();
         MP(init)(_value);
         _allocatedPrecision = MP(get_prec)(_value);
 
+        base = Math::Abs(base);
         IntPtr ptr = Marshal::StringToHGlobalAnsi(value);
-        bool success = 0 == MP(set_str)(_value, (char*)(void*)ptr, base);
+        bool success = 0 == MP(set_str)(_value, (char*)(void*)ptr, exponentInDecimal ? -base : base);
         Marshal::FreeHGlobal(ptr);
 
         if(!success)
@@ -88,10 +89,11 @@ namespace MPIR
         }
     }
 
-    void MPTYPE::SetTo(String^ value, int base)
+    void MPTYPE::SetTo(String^ value, int base, bool exponentInDecimal)
     {
+        base = Math::Abs(base);
         IntPtr ptr = Marshal::StringToHGlobalAnsi(value);
-        bool success = 0 == MP(set_str)(_value, (char*)(void*)ptr, base);
+        bool success = 0 == MP(set_str)(_value, (char*)(void*)ptr, exponentInDecimal ? -base : base);
         Marshal::FreeHGlobal(ptr);
 
         if(!success)
@@ -339,7 +341,82 @@ namespace MPIR
 
     size_t MPTYPE::Read(TextReader^ reader, int base, bool exponentInDecimal)
     {
-        throw gcnew NotImplementedException();
+        StringBuilder str;
+        
+        int c;
+        size_t nread = 0;
+        const unsigned char* digit_value = __gmp_digit_value_tab;
+        bool hasDecimal = false;
+        bool inExponent = false;
+
+        if (base < 2)
+            throw gcnew ArgumentException("Invalid base", "base");
+
+        if (base > 36)
+        {
+            // For bases > 36, use the collating sequence
+            // 0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz
+            digit_value += 224;
+            if (base > 62)
+                throw gcnew ArgumentException("Invalid base", "base");
+        }
+
+        // Skip whitespace
+        while ((c = reader->Peek()) >= 0 && Char::IsWhiteSpace(c))
+        {
+            nread++;
+            reader->Read();
+        }
+
+        // possibly negative
+        if (c == '-')
+        {
+            str.Append((wchar_t)c);
+            PEEK_NEXT_CHAR;
+        }
+
+        while (c != EOF)
+        {
+            if (c == '.')
+            {
+                if (hasDecimal) break;
+                
+                hasDecimal = true;
+                str.Append((wchar_t)c);
+                PEEK_NEXT_CHAR;
+                continue;
+            }
+
+            if ((base <= 10 && Char::ToLower(c) == 'e') || c == '@')
+            {
+                if (inExponent) break;
+                
+                inExponent = true;
+                str.Append((wchar_t)c);
+                PEEK_NEXT_CHAR;
+
+                // possibly negative
+                if (c == '-')
+                {
+                    str.Append((wchar_t)c);
+                    PEEK_NEXT_CHAR;
+                }
+                continue;
+            }
+
+            if (inExponent && exponentInDecimal && !Char::IsDigit(c))
+                break;
+
+            int dig = digit_value[c];
+            if (dig >= base)
+                break;
+
+            str.Append((wchar_t)c);
+            PEEK_NEXT_CHAR;
+        }
+
+        SetTo(str.ToString(), base, exponentInDecimal);
+        return str.Length + nread;
     }
 
     #pragma endregion
diff --git a/mpir.net/mpir.net/HugeFloat.h b/mpir.net/mpir.net/HugeFloat.h
index d4878917..b1832142 100644
--- a/mpir.net/mpir.net/HugeFloat.h
+++ b/mpir.net/mpir.net/HugeFloat.h
@@ -761,7 +761,7 @@ namespace MPIR
             {
                 _value = (MP(ptr))((*__gmp_allocate_func)(sizeof(MPSTRUCT)));
             }
-            void FromString(String^ value, int base);
+            void FromString(String^ value, int base, bool exponentInDecimal);
             MPTYPE(bool initialize);
             String^ ToString(int base, bool lowercase, int maxDigits, bool exponentInDecimal);
 
@@ -820,21 +820,33 @@ namespace MPIR
             static MPTYPE^ Allocate(mp_bitcnt_t precision);
 
             /// <summary>
-            /// Initializes a new float instance and sets its value from the specified string, using leading characters to recognize the base:
-            /// 0x and 0X for hexadecimal, 0b and 0B for binary, 0 for octal, or decimal otherwise.
+            /// Initializes a new float instance and sets its value from the specified string.
+            /// <para>No leading base characters are allowed.
+            /// </para>The exponent is always in decimal.
             /// </summary>
             /// <param name="value">string representing the initial value for the new instance.  Whitespace in the string is ignored.</param>
-            MPTYPE(String^ value) { FromString(value, 0); }
+            MPTYPE(String^ value) { FromString(value, 0, true); }
 
             /// <summary>
             /// Initializes a new float instance and sets its value from the specified string
             /// </summary>
             /// <param name="value">string representing the initial value for the new instance.  Whitespace in the string is ignored.</param>
             /// <param name="base">base the <paramref name="value"/> string is in.
-            /// <para>The base may vary from 2 to 62, or if base is 0, then the leading characters are used: 0x and 0X for hexadecimal, 0b and 0B for binary, 0 for octal, or decimal otherwise.
+            /// <para>The base may vary from 2 to 62.  No leading base characters are allowed.  The exponent is always in decimal
             /// </para>For bases up to 36, case is ignored; upper-case and lower-case letters have the same value. 
             /// For bases 37 to 62, upper-case letter represent the usual 10..35 while lower-case letter represent 36..61.</param>
-            MPTYPE(String^ value, int base) { FromString(value, base); }
+            MPTYPE(String^ value, int base) { FromString(value, base, true); }
+
+            /// <summary>
+            /// Initializes a new float instance and sets its value from the specified string
+            /// </summary>
+            /// <param name="value">string representing the initial value for the new instance.  Whitespace in the string is ignored.</param>
+            /// <param name="base">base the <paramref name="value"/> string is in.
+            /// <para>The base may vary from 2 to 62.  No leading base characters are allowed.
+            /// </para>For bases up to 36, case is ignored; upper-case and lower-case letters have the same value. 
+            /// For bases 37 to 62, upper-case letter represent the usual 10..35 while lower-case letter represent 36..61.</param>
+            /// <param name="exponentInDecimal">True if the exponent is in decimal, false to use the same base as the mantissa.</param>
+            MPTYPE(String^ value, int base, bool exponentInDecimal) { FromString(value, base, exponentInDecimal); }
 
             /// <summary>
             /// Initializes a new float instance and sets its value to the result of computing the source expression.
@@ -1049,11 +1061,24 @@ namespace MPIR
             /// </para>If the fraction is not in canonical form, Canonicalize() must be called.
             /// </summary>
             /// <param name="value">new value for the object</param>
-            /// <param name="base">base the <paramref name="value"/> string is in.
-            /// <para>The base may vary from 2 to 62, or if base is 0, then the leading characters are used: 0x and 0X for hexadecimal, 0b and 0B for binary, 0 for octal, or decimal otherwise.
+            /// <param name="base">base the mantissa in the <paramref name="value"/> string is in.  Exponent is always in decimcal.
+            /// <para>The base may vary from 2 to 62.  No leading leading base characters are allowed.
             /// </para>For bases up to 36, case is ignored; upper-case and lower-case letters have the same value. 
             /// For bases 37 to 62, upper-case letter represent the usual 10..35 while lower-case letter represent 36..61.</param>
-            void SetTo(String^ value, int base);
+            void SetTo(String^ value, int base) { SetTo(value, base, true); }
+
+            /// <summary>
+            /// Sets the value of the float object.
+            /// <para>Do not change the value of an object while it is contained in a hash table, because that changes its hash code.
+            /// </para>If the fraction is not in canonical form, Canonicalize() must be called.
+            /// </summary>
+            /// <param name="value">new value for the object</param>
+            /// <param name="base">base the <paramref name="value"/> string is in.
+            /// <para>The base may vary from 2 to 62.  No leading leading base characters are allowed.
+            /// </para>For bases up to 36, case is ignored; upper-case and lower-case letters have the same value. 
+            /// For bases 37 to 62, upper-case letter represent the usual 10..35 while lower-case letter represent 36..61.</param>
+            /// <param name="exponentInDecimal">If true, the exponent is in decimal; otherwise it is in the same base as the mantissa</param>
+            void SetTo(String^ value, int base, bool exponentInDecimal);
 
             /// <summary>
             /// Sets the value of the float object.