Export (0) Print
Expand All

Convert.ToInt64 Method (Double)

Converts the value of the specified double-precision floating-point number to an equivalent 64-bit signed integer.

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

public static long ToInt64(
	double value
)

Parameters

value
Type: System.Double

The double-precision floating-point number to convert.

Return Value

Type: System.Int64
value, rounded to the nearest 64-bit signed integer. If value is halfway between two whole numbers, the even number is returned; that is, 4.5 is converted to 4, and 5.5 is converted to 6.

ExceptionCondition
OverflowException

value is greater than Int64.MaxValue or less than Int64.MinValue.

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

double[] values= { Double.MinValue, -1.38e10, -1023.299, -12.98,
                   0, 9.113e-16, 103.919, 17834.191, Double.MaxValue };
long result;

foreach (double value in values)
{
   try {
      result = Convert.ToInt64(value);
      Console.WriteLine("Converted the {0} value '{1}' to the {2} value {3}.",
                        value.GetType().Name, value,
                        result.GetType().Name, result);
   }
   catch (OverflowException) {
      Console.WriteLine("{0} is outside the range of the Int64 type.", value);
   }   
}                                 
//    -1.79769313486232E+308 is outside the range of the Int64 type. 
//    -13800000000 is outside the range of the Int16 type. 
//    Converted the Double value '-1023.299' to the Int64 value -1023. 
//    Converted the Double value '-12.98' to the Int64 value -13. 
//    Converted the Double value '0' to the Int64 value 0. 
//    Converted the Double value '9.113E-16' to the Int64 value 0. 
//    Converted the Double value '103.919' to the Int64 value 104. 
//    Converted the Double value '17834.191' to the Int64 value 17834. 
//    1.79769313486232E+308 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