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Decimal Explicit Conversion (Decimal to UInt64)

Converts a Decimal to a 64-bit unsigned integer.

This API is not CLS-compliant. 

Namespace:  System
Assembly:  mscorlib (in mscorlib.dll)

public static explicit operator ulong (
	decimal value


Type: System.Decimal
A Decimal to convert.

Return Value

Type: System.UInt64
A 64-bit unsigned integer that represents the converted Decimal.


value is negative or greater than UInt64.MaxValue.

This operator supports the explicit conversion of a Decimal to a UInt64. The syntax for such explicit conversions is language-dependent, and individual language compilers can provide different implementations and return different results. The example illustrates the different return values when you explicitly convert a Decimal value to a UInt64 value by using C# and Visual Basic. To perform a conversion that is independent of language, you can call the ToUInt64 or the Convert.ToUInt64(Decimal) method.

The following code example converts Decimal numbers to UInt64 values using the explicit Decimal to UInt64 conversion.

// Example of the explicit conversions from decimal to long and 
// decimal to ulong.
using System;

class Example
   const string formatter = "{0,25}{1,22}{2,22}";

   // Get the exception type name; remove the namespace prefix.
   public static string GetExceptionType(Exception ex)
      string exceptionType = ex.GetType().ToString();
      return exceptionType.Substring(
          exceptionType.LastIndexOf('.') + 1);

   // Convert the decimal argument; catch exceptions that are thrown.
   public static void DecimalToU_Int64(System.Windows.Controls.TextBlock outputBlock, decimal argument)
      object Int64Value;
      object UInt64Value;

      // Convert the argument to a long value.
         Int64Value = (long)argument;
      catch (Exception ex)
         Int64Value = GetExceptionType(ex);

      // Convert the argument to a ulong value.
         UInt64Value = (ulong)argument;
      catch (Exception ex)
         UInt64Value = GetExceptionType(ex);

      outputBlock.Text += String.Format(formatter, argument,
          Int64Value, UInt64Value) + "\n";

   public static void Demo(System.Windows.Controls.TextBlock outputBlock)
      outputBlock.Text += String.Format(
          "This example of the explicit conversions from decimal " +
          "to long \nand decimal to ulong generates the following " +
          "output. It displays \nseveral converted decimal " +
          "values.\n") + "\n";
      outputBlock.Text += String.Format(formatter, "decimal argument",
          "long/exception", "ulong/exception") + "\n";
      outputBlock.Text += String.Format(formatter, "----------------",
          "--------------", "---------------") + "\n";

      // Convert decimal values and display the results.
      DecimalToU_Int64(outputBlock, 123M);
      DecimalToU_Int64(outputBlock, new decimal(123000, 0, 0, false, 3));
      DecimalToU_Int64(outputBlock, 123.999M);
      DecimalToU_Int64(outputBlock, 18446744073709551615.999M);
      DecimalToU_Int64(outputBlock, 18446744073709551616M);
      DecimalToU_Int64(outputBlock, 9223372036854775807.999M);
      DecimalToU_Int64(outputBlock, 9223372036854775808M);
      DecimalToU_Int64(outputBlock, -0.999M);
      DecimalToU_Int64(outputBlock, -1M);
      DecimalToU_Int64(outputBlock, -9223372036854775808.999M);
      DecimalToU_Int64(outputBlock, -9223372036854775809M);

This example of the explicit conversions from decimal to long
and decimal to ulong generates the following output. It displays
several converted decimal values.

         decimal argument        long/exception       ulong/exception
         ----------------        --------------       ---------------
                      123                   123                   123
                  123.000                   123                   123
                  123.999                   123                   123
 18446744073709551615.999     OverflowException  18446744073709551615
     18446744073709551616     OverflowException     OverflowException
  9223372036854775807.999   9223372036854775807   9223372036854775807
      9223372036854775808     OverflowException   9223372036854775808
                   -0.999                     0                     0
                       -1                    -1     OverflowException
 -9223372036854775808.999  -9223372036854775808     OverflowException
     -9223372036854775809     OverflowException     OverflowException


Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

XNA Framework

Supported in: Xbox 360, Windows Phone OS 7.0

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.

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