System.Numerics.Tests.cast_fromTest.RunDecimalExplicitCastFromBigIntegerTests C# (CSharp) Method

        public static void RunDecimalExplicitCastFromBigIntegerTests()
        {
            int[] bits = new int[3];
            uint temp2;
            bool carry;
            byte[] temp;
            Decimal value;
            BigInteger bigInteger;

            // Decimal Explicit Cast from BigInteger: Random value < Decimal.MinValue
            for (int i = 0; i < NumberOfRandomIterations; ++i)
            {
                bigInteger = GenerateRandomBigIntegerLessThan(Decimal.MinValue, s_random);
                temp = bigInteger.ToByteArray();
                carry = true;
                for (int j = 0; j < 3; j++)
                {
                    temp2 = BitConverter.ToUInt32(temp, 4 * j);
                    temp2 = ~temp2;
                    if (carry)
                    {
                        carry = false;
                        temp2 += 1;
                        if (temp2 == 0)
                        {
                            carry = true;
                        }
                    }
                    bits[j] = (int)temp2;
                }
                value = new Decimal(bits[0], bits[1], bits[2], true, 0);
                Assert.Throws<OverflowException>(() => VerifyDecimalExplicitCastFromBigInteger(value, bigInteger));
            }

            // Decimal Explicit Cast from BigInteger: Decimal.MinValue - 1
            bigInteger = new BigInteger(Decimal.MinValue);
            bigInteger -= BigInteger.One;
            temp = bigInteger.ToByteArray();
            carry = true;
            for (int j = 0; j < 3; j++)
            {
                temp2 = BitConverter.ToUInt32(temp, 4 * j);
                temp2 = ~temp2;
                if (carry)
                {
                    carry = false;
                    temp2 += 1;
                    if (temp2 == 0)
                    {
                        carry = true;
                    }
                }
                bits[j] = (int)temp2;
            }
            value = new Decimal(bits[0], bits[1], bits[2], true, 0);
            Assert.Throws<OverflowException>(() => VerifyDecimalExplicitCastFromBigInteger(value, bigInteger));

            // Decimal Explicit Cast from BigInteger: Decimal.MinValue
            VerifyDecimalExplicitCastFromBigInteger(Decimal.MinValue);

            // Decimal Explicit Cast from BigInteger: Random Negative
            for (int i = 0; i < NumberOfRandomIterations; ++i)
            {
                VerifyDecimalExplicitCastFromBigInteger(((Decimal)((Double)Decimal.MaxValue * s_random.NextDouble())) - Decimal.MaxValue);
            }

            // Decimal Explicit Cast from BigInteger: Random Negative Non-Integral > -100
            for (int i = 0; i < NumberOfRandomIterations; ++i)
            {
                value = (Decimal)(100 * s_random.NextDouble() - 100);
                VerifyDecimalExplicitCastFromBigInteger(Decimal.Truncate(value), new BigInteger(value));
            }

            // Decimal Explicit Cast from BigInteger: -1
            VerifyDecimalExplicitCastFromBigInteger(-1);

            // Decimal Explicit Cast from BigInteger: 0
            VerifyDecimalExplicitCastFromBigInteger(0);

            // Decimal Explicit Cast from BigInteger: 1
            VerifyDecimalExplicitCastFromBigInteger(1);

            // Decimal Explicit Cast from BigInteger: Random Positive Non-Integral < 100
            for (int i = 0; i < NumberOfRandomIterations; ++i)
            {
                value = (Decimal)(100 * s_random.NextDouble());
                VerifyDecimalExplicitCastFromBigInteger(Decimal.Truncate(value), new BigInteger(value));
            }

            // Decimal Explicit Cast from BigInteger: Random Positive
            for (int i = 0; i < NumberOfRandomIterations; ++i)
            {
                VerifyDecimalExplicitCastFromBigInteger((Decimal)((Double)Decimal.MaxValue * s_random.NextDouble()));
            }

            // Decimal Explicit Cast from BigInteger: Decimal.MaxValue
            VerifyDecimalExplicitCastFromBigInteger(Decimal.MaxValue);

            // Decimal Explicit Cast from BigInteger: Decimal.MaxValue + 1
            bigInteger = new BigInteger(Decimal.MaxValue);
            bigInteger += BigInteger.One;
            temp = bigInteger.ToByteArray();
            for (int j = 0; j < 3; j++)
            {
                bits[j] = BitConverter.ToInt32(temp, 4 * j);
            }
            value = new Decimal(bits[0], bits[1], bits[2], false, 0);
            Assert.Throws<OverflowException>(() => VerifyDecimalExplicitCastFromBigInteger(value, bigInteger));

            // Decimal Explicit Cast from BigInteger: Random value > Decimal.MaxValue
            for (int i = 0; i < NumberOfRandomIterations; ++i)
            {
                bigInteger = GenerateRandomBigIntegerGreaterThan(Decimal.MaxValue, s_random);
                temp = bigInteger.ToByteArray();
                for (int j = 0; j < 3; j++)
                {
                    bits[j] = BitConverter.ToInt32(temp, 4 * j);
                }
                value = new Decimal(bits[0], bits[1], bits[2], false, 0);
                Assert.Throws<OverflowException>(() => VerifyDecimalExplicitCastFromBigInteger(value, bigInteger));
            }
        }