C＃中的Decimal.ToDouble()方法

此方法用于将指定的Decimal的值转换为等效的双精度浮点数。此方法可能会产生舍入错误，因为双精度浮点数的有效位数比十进制数少。

Syntax: public static double ToDouble (decimal d);
Here, d is the decimal value which is to be converted.

Return value: It returns a double-precision floating-point number equivalent to d.

例子：

// C# program to demonstrate the
// Decimal.ToDouble(Decimal) Method
using System;
  
class GFG {
  
    // Main Method
    public static void Main()
    {
        try {
  
            // Taking decimal variables
            Decimal dec1 = 0.0000000000134563456789M;
            Decimal dec2 = 4589662514452860951234M;
  
            // using ToDouble(Decimal) Method
            Double val1 = Decimal.ToDouble(dec1);
              
            // using ToDouble(Decimal) Method
            Double val2 = Decimal.ToDouble(dec2);
  
            // Printing the Double value
            Console.WriteLine("The Double value "
                              + "is : {0}", val1);
                                
            // Printing the Double value
            Console.WriteLine("The Double value "
                              + "is : {0}", val2);
                          
        }
  
        catch (OverflowException e) 
        {
            Console.Write("Exception Thrown: ");
            Console.Write("{0}", e.GetType(), e.Message);
        }
    }
}

输出：

The Double value is : 1.34563456789E-11
The Double value is : 4.58966251445286E+21

参考：

• https://docs.microsoft.com/zh-cn/dotnet/api/system.decimal.todouble?view=netframework-4.7.2