c# - 具有十进制格式的C#string.format。

Question

DriveInfo[] drives = DriveInfo.GetDrives();
for (int i = 0; i < drives.Length; i++)
{
    if (drives[i].IsReady)
    {
        Console.WriteLine("Drive {0} - Has free space of {1} GB",drives[i].ToString(),(drives[i].TotalFreeSpace/1024/1024/1024).ToString("N2"));
    }
}

输出：

Drive C:\ - Has free space of 70,00 GB
Drive D:\ - Has free space of 31,00 GB
Drive E:\ - Has free space of 7,00 GB
Drive F:\ - Has free space of 137,00 GB

全部以，00结尾，但我需要显示实际大小。那么哪种格式合适呢？

Answer 1

格式字符串与它无关。您的整数运算将舍弃任何余数。

3920139012 / 1024 / 1024  / 1024 // 3

使用 m后缀指定小数，如下所示：

3920139012 / 1024m / 1024m / 1024m // 3.6509139575064182281494140625

或者：

3920139012 / Math.Pow(1024, 3) // 3.65091395750642

这可能更清楚一些：

var gb = Math.Pow(1024, 3);
foreach(var drive in DriveInfo.GetDrives())
{   
    if(drive.IsReady)
    {
        Console.WriteLine("Drive {0} - Has free space of {1:n2} GB",
            drive.Name,
            drive.TotalFreeSpace / gb);
    }
}