 using System;
using System.ComponentModel;
using System.Diagnostics;
using System.Runtime.InteropServices;
using System.Security.Principal;
using System.Threading;
using System.Collections.Generic;

namespace FreeMemory
{
//Declaration of structures
//SYSTEM_CACHE_INFORMATION
[StructLayout(LayoutKind.Sequential, Pack = 1)]
struct SYSTEM_CACHE_INFORMATION
{
    public uint CurrentSize;
    public uint PeakSize;
    public uint PageFaultCount;
    public uint MinimumWorkingSet;
    public uint MaximumWorkingSet;
    public uint Unused1;
    public uint Unused2;
    public uint Unused3;
    public uint Unused4;
}

//SYSTEM_CACHE_INFORMATION_64_BIT
[StructLayout(LayoutKind.Sequential, Pack = 1)]
struct SYSTEM_CACHE_INFORMATION_64_BIT
{
    public long CurrentSize;
    public long PeakSize;
    public long PageFaultCount;
    public long MinimumWorkingSet;
    public long MaximumWorkingSet;
    public long Unused1;
    public long Unused2;
    public long Unused3;
    public long Unused4;
}

//TokPriv1Luid
[StructLayout(LayoutKind.Sequential, Pack = 1)]
internal struct TokPriv1Luid
{
    public int Count;
    public long Luid;
    public int Attr;
}
public class Program
{
    //Declaration of constants
    const int SE_PRIVILEGE_ENABLED = 2;
    const string SE_INCREASE_QUOTA_NAME = "SeIncreaseQuotaPrivilege";
    const string SE_PROFILE_SINGLE_PROCESS_NAME = "SeProfileSingleProcessPrivilege";
    const int SystemFileCacheInformation = 0x0015;
    const int SystemMemoryListInformation = 0x0050;
    const int MemoryPurgeStandbyList = 4;
    const int MemoryEmptyWorkingSets = 2;

    //Import of DLL's (API) and the necessary functions 
    [DllImport("advapi32.dll", SetLastError = true)]
    internal static extern bool LookupPrivilegeValue(string host, string name, ref long pluid);

    [DllImport("advapi32.dll", SetLastError = true)]
    internal static extern bool AdjustTokenPrivileges(IntPtr htok, bool disall, ref TokPriv1Luid newst, int len, IntPtr prev, IntPtr relen);

    [DllImport("ntdll.dll")]
    public static extern UInt32 NtSetSystemInformation(int InfoClass, IntPtr Info, int Length);

    [DllImport("psapi.dll")]
    static extern int EmptyWorkingSet(IntPtr hwProc);

    //Function to clear working set of all processes
    public static void EmptyWorkingSetFunction()
    {
        //Declaration of variables
        string ProcessName = string.Empty;
        Process[] allProcesses = Process.GetProcesses();
        List<string> successProcesses = new List<string>();
        List<string> failProcesses = new List<string>();

        //Cycle through all processes
        for (int i = 0; i < allProcesses.Length; i++)
        {
            Process p = new Process();
            p = allProcesses[i];
            //Try to empty the working set of the process, if succesfull add to successProcesses, if failed add to failProcesses with error message
            try
            {
                ProcessName = p.ProcessName;
                EmptyWorkingSet(p.Handle);
                successProcesses.Add(ProcessName);
            }
            catch (Exception ex)
            {
                failProcesses.Add(ProcessName + ": " + ex.Message);
            }
        }

        //Print the lists with successful and failed processes
        Console.WriteLine("SUCCESSFULLY CLEARED PROCESSES: " + successProcesses.Count);
        Console.WriteLine("-------------------------------");
        for (int i = 0; i < successProcesses.Count; i++)
        {
            Console.WriteLine(successProcesses[i]);
        }
        Console.WriteLine();

        Console.WriteLine("FAILED CLEARED PROCESSES: " + failProcesses.Count);
        Console.WriteLine("-------------------------------");
        for (int i = 0; i < failProcesses.Count; i++)
        {
            Console.WriteLine(failProcesses[i]);
        }
        Console.WriteLine();
    }

    //Function to check if OS is 64-bit or not, returns boolean
    public static bool Is64BitMode()
    {
        return Marshal.SizeOf(typeof(IntPtr)) == 8;
    }

    //Function used to clear file system cache, returns boolean
    public static void ClearFileSystemCache(bool ClearStandbyCache)
    {
        try
        {
            //Check if privilege can be increased
            if (SetIncreasePrivilege(SE_INCREASE_QUOTA_NAME))
            {
                uint num1;
                int SystemInfoLength;
                GCHandle gcHandle;
                //First check which version is running, then fill structure with cache information. Throw error is cache information cannot be read.
                if (!Is64BitMode())
                {
                    SYSTEM_CACHE_INFORMATION cacheInformation = new SYSTEM_CACHE_INFORMATION();
                    cacheInformation.MinimumWorkingSet = uint.MaxValue;
                    cacheInformation.MaximumWorkingSet = uint.MaxValue;
                    SystemInfoLength = Marshal.SizeOf(cacheInformation);
                    gcHandle = GCHandle.Alloc(cacheInformation, GCHandleType.Pinned);
                    num1 = NtSetSystemInformation(SystemFileCacheInformation, gcHandle.AddrOfPinnedObject(), SystemInfoLength);
                    gcHandle.Free();
                }
                else
                {
                    SYSTEM_CACHE_INFORMATION_64_BIT information64Bit = new SYSTEM_CACHE_INFORMATION_64_BIT();
                    information64Bit.MinimumWorkingSet = -1L;
                    information64Bit.MaximumWorkingSet = -1L;
                    SystemInfoLength = Marshal.SizeOf(information64Bit);
                    gcHandle = GCHandle.Alloc(information64Bit, GCHandleType.Pinned);
                    num1 = NtSetSystemInformation(SystemFileCacheInformation, gcHandle.AddrOfPinnedObject(), SystemInfoLength);
                    gcHandle.Free();
                }
                if (num1 != 0)
                    throw new Exception("NtSetSystemInformation(SYSTEMCACHEINFORMATION) error: ", new Win32Exception(Marshal.GetLastWin32Error()));
            }

            //If passes paramater is 'true' and the privilege can be increased, then clear standby lists through MemoryPurgeStandbyList
            if (ClearStandbyCache && SetIncreasePrivilege(SE_PROFILE_SINGLE_PROCESS_NAME))
            {
                int SystemInfoLength = Marshal.SizeOf(MemoryPurgeStandbyList);
                GCHandle gcHandle = GCHandle.Alloc(MemoryPurgeStandbyList, GCHandleType.Pinned);
                uint num2 = NtSetSystemInformation(SystemMemoryListInformation, gcHandle.AddrOfPinnedObject(), SystemInfoLength);
                gcHandle.Free();
                if (num2 != 0)
                    throw new Exception("NtSetSystemInformation(SYSTEMMEMORYLISTINFORMATION) error: ", new Win32Exception(Marshal.GetLastWin32Error()));
            }
        }
        catch (Exception ex)
        {
            Console.Write(ex.ToString());
        }
    }

    //Function to increase Privilege, returns boolean
    private static bool SetIncreasePrivilege(string privilegeName)
    {
        using (WindowsIdentity current = WindowsIdentity.GetCurrent(TokenAccessLevels.Query | TokenAccessLevels.AdjustPrivileges))
        {
            TokPriv1Luid newst;
            newst.Count = 1;
            newst.Luid = 0L;
            newst.Attr = SE_PRIVILEGE_ENABLED;

            //Retrieves the LUID used on a specified system to locally represent the specified privilege name
            if (!LookupPrivilegeValue(null, privilegeName, ref newst.Luid))
                throw new Exception("Error in LookupPrivilegeValue: ", new Win32Exception(Marshal.GetLastWin32Error()));

            //Enables or disables privileges in a specified access token
            int num = AdjustTokenPrivileges(current.Token, false, ref newst, 0, IntPtr.Zero, IntPtr.Zero) ? 1 : 0;
            if (num == 0)
                throw new Exception("Error in AdjustTokenPrivileges: ", new Win32Exception(Marshal.GetLastWin32Error()));
            return num != 0;
        }
    }

    //MAIN Program
    static void Main(string[] args)
    {
        //Clear working set of all processes
        EmptyWorkingSetFunction();

        //Clear file system cache
        ClearFileSystemCache(true);

        //Waiting for input of user to close program
        Console.WriteLine("Press any key to exit.");
        Console.ReadKey();
    }
}
}

created 1 year ago by Ramton King

C Sharp Online Compiler

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Read inputs from stdin

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using System;
 
namespace Sample
{
  class Test
    {
      public static void Main(string[] args)
       {
         string name;
         name = Console.ReadLine();
         Console.WriteLine("Hello {0} ", name);
	}
     }
}

About C Sharp

C# is a general purpose object-oriented programming language by Microsoft. Though initially it was developed as part of .net but later it was approved by ECMA and ISO standards.

You can use C# to create variety of applications, like web, windows, mobile, console applications and much more using Visual studio.

Syntax help

Data types

Data Type	Description	Range	size
int	To store integers	-2,147,483,648 to 2,147,483,647	4 bytes
double	to store large floating point numbers with decimals	can store 15 decimal digits	8 bytes
float	to store floating point numbers with decimals	can store upto 7 decimal digits	4 bytes
char	to store single characters	-	2 bytes
string	to stores text	-	2 bytes per character
bool	to stores either true or false	-	1 bit

Variables

Syntax

datatype variable-name = value;

Loops

1. If-Else:

When ever you want to perform a set of operations based on a condition or set of few conditions IF-ELSE is used.

if(conditional-expression) {
   // code
} 
else {
   // code
}

You can also use if-else for nested Ifs and If-Else-If ladder when multiple conditions are to be performed on a single variable.

2. Switch:

Switch is an alternative to If-Else-If ladder.

switch(conditional-expression) {    
case value1:    
 // code    
 break;  // optional  
case value2:    
 // code    
 break;  // optional  
...    
    
default:     
 // code to be executed when all the above cases are not matched;    
}

3. For:

For loop is used to iterate a set of statements based on a condition.

for(Initialization; Condition; Increment/decrement) {
  // code  
}

4. While:

While is also used to iterate a set of statements based on a condition. Usually while is preferred when number of iterations are not known in advance.

while(condition) {
 // code 
}

5. Do-While:

Do-while is also used to iterate a set of statements based on a condition. It is mostly used when you need to execute the statements atleast once.

do {
  // code 
} while (condition);

Arrays

Array is a collection of similar data which is stored in continuous memory addresses. Array values can be fetched using index. Index starts from 0 to size-1.

Syntax

data-type[] array-name;

Methods

Method is a set of statements which gets executed only when they are called. Call the method name in the main function to execute the method.

Syntax

static void method-name() 
{
  // code to be executed
}