Convert.ToInt64 Method (Double)

 

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

Namespace:   System
Assembly:  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.

Exception Condition
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.

Universal Windows Platform
Available since 8
.NET Framework
Available since 1.1
Portable Class Library
Supported in: portable .NET platforms
Silverlight
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1
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