Was this page helpful?
Your feedback about this content is important. Let us know what you think.
Additional feedback?
1500 characters remaining
Export (0) Print
Expand All

Convert.ToInt64 Method (UInt64)

Converts the value of the specified 64-bit unsigned integer to an equivalent 64-bit signed integer.

This API is not CLS-compliant. 

Namespace:  System
Assemblies:   System.Runtime.Extensions (in System.Runtime.Extensions.dll)
  mscorlib (in mscorlib.dll)

[CLSCompliantAttribute(false)]
public static long ToInt64(
	ulong value
)

Parameters

value
Type: System.UInt64

The 64-bit unsigned integer to convert.

Return Value

Type: System.Int64
A 64-bit signed integer that is equivalent to value.

ExceptionCondition
OverflowException

value is greater than Int64.MaxValue.

The following example attempts to convert each element in an array of unsigned long integers to a long integer.

ulong[] numbers = { UInt64.MinValue, 121, 340, UInt64.MaxValue };
long result;
foreach (ulong number in numbers)
{
   try {
      result = Convert.ToInt64(number);
      Console.WriteLine("Converted the {0} value {1} to a {2} value {3}.",
                        number.GetType().Name, number,
                        result.GetType().Name, result);
   }
   catch (OverflowException) {
      Console.WriteLine("The {0} value {1} is outside the range of the Int64 type.",
                        number.GetType().Name, number);
   }
}
// The example displays the following output: 
//    Converted the UInt64 value 0 to a Int32 value 0. 
//    Converted the UInt64 value 121 to a Int32 value 121. 
//    Converted the UInt64 value 340 to a Int32 value 340. 
//    The UInt64 value 18446744073709551615 is outside the range of the Int64 type.

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0, 1.1

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

XNA Framework

Supported in: 3.0, 2.0, 1.0

Portable Class Library

Supported in: Portable Class Library

Supported in: Windows Phone 8.1

Supported in: Windows Phone Silverlight 8.1

Supported in: Windows Phone Silverlight 8
Show:
© 2015 Microsoft