C# 代码调整屏幕分辨率

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Runtime.InteropServices;
namespace 解决分辨率
{
public partial class Form1 : Form
{
//保存当前屏幕分辨率
int i = Screen.PrimaryScreen.Bounds.Width;
int j = Screen.PrimaryScreen.Bounds.Height;
public Form1()
{
InitializeComponent();
}
[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Auto)]
public struct DEVMODE
{
[MarshalAs(UnmanagedType.ByValTStr, SizeConst = 32)]
public string dmDeviceName;
public short dmSpecVersion;
public short dmDriverVersion;
public short dmSize;
public short dmDriverExtra;
public int dmFields;
public short dmOrientation;
public short dmPaperSize;
public short dmPaperLength;
public short dmPaperWidth;
public short dmScale;
public short dmCopies;
public short dmDefaultSource;
public short dmPrintQuality;
public short dmColor;
public short dmDuplex;
public short dmYResolution;
public short dmTTOption;
public short dmCollate;
[MarshalAs(UnmanagedType.ByValTStr, SizeConst = 32)]
public string dmFormName;
public short dmLogPixels;
public int dmBitsPerPel;
public int dmPelsWidth;
public int dmPelsHeight;
public int dmDisplayFlags;
public int dmDisplayFrequency;
}
[DllImport("user32.dll", CharSet = CharSet.Auto)]
static extern int ChangeDisplaySettings([In] ref DEVMODE lpDevMode, int dwFlags);
[DllImport("user32.dll", CharSet = CharSet.Auto)]
static extern bool EnumDisplaySettings(string lpszDeviceName, Int32 iModeNum, ref DEVMODE lpDevMode);
void ChangeRes()
{

DEVMODE DevM = new DEVMODE();
DevM.dmSize = (short)Marshal.SizeOf(typeof(DEVMODE));
bool mybool;
mybool = EnumDisplaySettings(null, 0, ref DevM);
DevM.dmPelsWidth = 1024;//宽
DevM.dmPelsHeight = 768;//高
DevM.dmDisplayFrequency = 60;//刷新频率
DevM.dmBitsPerPel = 32;//颜色象素
long result = ChangeDisplaySettings(ref DevM, 0);
}
void FuYuan()
{
DEVMODE DevM = new DEVMODE();
DevM.dmSize = (short)Marshal.SizeOf(typeof(DEVMODE));
bool mybool;
mybool = EnumDisplaySettings(null, 0, ref DevM);
DevM.dmPelsWidth = i;//恢复宽
DevM.dmPelsHeight =j;//恢复高
DevM.dmDisplayFrequency = 60;//刷新频率
DevM.dmBitsPerPel = 32;//颜色象素
long result = ChangeDisplaySettings(ref DevM, 0);
}
private void Form1_Load(object sender, EventArgs e)
{
ChangeRes();
}

private void button1_Click(object sender, EventArgs e)
{
FuYuan();
this.Close();

}