Get free disk space

Question

Given each of the inputs below, I\'d like to get free space on that location. Something like

long GetFreeSpace(string path)

Inputs:

Answer 1

untested:

using System;
using System.Management;

ManagementObject disk = new
ManagementObject("win32_logicaldisk.deviceid="c:"");
disk.Get();
Console.WriteLine("Logical Disk Size = " + disk["Size"] + " bytes");
Console.WriteLine("Logical Disk FreeSpace = " + disk["FreeSpace"] + "
bytes"); 

Btw what is the outcome of free diskspace on c:\temp ? you will get the space free of c:\

Answer 2

Working code snippet using GetDiskFreeSpaceEx from link by RichardOD.

// Pinvoke for API function
[DllImport("kernel32.dll", SetLastError = true, CharSet = CharSet.Auto)]
[return: MarshalAs(UnmanagedType.Bool)]
public static extern bool GetDiskFreeSpaceEx(string lpDirectoryName,
out ulong lpFreeBytesAvailable,
out ulong lpTotalNumberOfBytes,
out ulong lpTotalNumberOfFreeBytes);

public static bool DriveFreeBytes(string folderName, out ulong freespace)
{
    freespace = 0;
    if (string.IsNullOrEmpty(folderName))
    {
        throw new ArgumentNullException("folderName");
    }

    if (!folderName.EndsWith("\\"))
    {
        folderName += '\\';
    }

    ulong free = 0, dummy1 = 0, dummy2 = 0;

    if (GetDiskFreeSpaceEx(folderName, out free, out dummy1, out dummy2))
    {
        freespace = free;
        return true;
    }
    else
    {
        return false;
    }
}

Answer 3

I wanted a similar method for my project but in my case the input paths were either from local disk volumes or clustered storage volumes (CSVs). So DriveInfo class did not work for me. CSVs have a mount point under another drive, typically C:\ClusterStorage\Volume*. Note that C: will be a different Volume than C:\ClusterStorage\Volume1

This is what I finally came up with:

    public static ulong GetFreeSpaceOfPathInBytes(string path)
    {
        if ((new Uri(path)).IsUnc)
        {
            throw new NotImplementedException("Cannot find free space for UNC path " + path);
        }

        ulong freeSpace = 0;
        int prevVolumeNameLength = 0;

        foreach (ManagementObject volume in
                new ManagementObjectSearcher("Select * from Win32_Volume").Get())
        {
            if (UInt32.Parse(volume["DriveType"].ToString()) > 1 &&                             // Is Volume monuted on host
                volume["Name"] != null &&                                                       // Volume has a root directory
                path.StartsWith(volume["Name"].ToString(), StringComparison.OrdinalIgnoreCase)  // Required Path is under Volume's root directory 
                )
            {
                // If multiple volumes have their root directory matching the required path,
                // one with most nested (longest) Volume Name is given preference.
                // Case: CSV volumes monuted under other drive volumes.

                int currVolumeNameLength = volume["Name"].ToString().Length;

                if ((prevVolumeNameLength == 0 || currVolumeNameLength > prevVolumeNameLength) &&
                    volume["FreeSpace"] != null
                    )
                {
                    freeSpace = ulong.Parse(volume["FreeSpace"].ToString());
                    prevVolumeNameLength = volume["Name"].ToString().Length;
                }
            }
        }

        if (prevVolumeNameLength > 0)
        {
            return freeSpace;
        }

        throw new Exception("Could not find Volume Information for path " + path);
    }

Answer 4

DriveInfo will help you with some of those (but it doesn't work with UNC paths), but really I think you will need to use GetDiskFreeSpaceEx. You can probably achieve some functionality with WMI. GetDiskFreeSpaceEx looks like your best bet.

Chances are you will probably have to clean up your paths to get it to work properly.

Answer 5

As this answer and @RichardOD suggested , you should do like this:

[DllImport("kernel32.dll", SetLastError=true, CharSet=CharSet.Auto)]
[return: MarshalAs(UnmanagedType.Bool)]
static extern bool GetDiskFreeSpaceEx(string lpDirectoryName,
   out ulong lpFreeBytesAvailable,
   out ulong lpTotalNumberOfBytes,
   out ulong lpTotalNumberOfFreeBytes);

ulong FreeBytesAvailable;
ulong TotalNumberOfBytes;
ulong TotalNumberOfFreeBytes;

bool success = GetDiskFreeSpaceEx(@"\\mycomputer\myfolder",
                                  out FreeBytesAvailable,
                                  out TotalNumberOfBytes,
                                  out TotalNumberOfFreeBytes);
if(!success)
    throw new System.ComponentModel.Win32Exception();

Console.WriteLine("Free Bytes Available:      {0,15:D}", FreeBytesAvailable);
Console.WriteLine("Total Number Of Bytes:     {0,15:D}", TotalNumberOfBytes);
Console.WriteLine("Total Number Of FreeBytes: {0,15:D}", TotalNumberOfFreeBytes);

Answer 6

You can try this:

var driveName = "C:\\";
var freeSpace = DriveInfo.GetDrives().Where(x => x.Name == driveName && x.IsReady).FirstOrDefault().TotalFreeSpace;

Good luck