Question

c# 返回指点坐标点颜色的代码，请指教

using System;
using System.Drawing;
using System.Runtime.InteropServices;

namespace cs
{
public class cs
{
[DllImport("user32", ExactSpelling = true, CharSet = CharSet.Ansi, SetLastError = true)]
private static extern int WindowFromPoint(int xPoint, int yPoint);
//指定点窗口的句柄
[DllImport("user32", ExactSpelling = true, CharSet = CharSet.Ansi, SetLastError = true)]
private static extern int GetDC(int hwnd);
//获取屏幕DC（这个咧自己想的）
[DllImport("gdi32", ExactSpelling = true, CharSet = CharSet.Ansi, SetLastError = true)]
private static extern int GetPixel(int hdc, int X, int y);
//获取屏幕指定点的颜色
public Color GetColor(int x, int y)
{
int hdc = GetDC(IntPtr .Zero );
uint pixel = GetPixel(hdc, x, y);
ReleaseDC(IntPtr.Zero, hdc);
Color color = Color.FromArgb((int)(pixel & 0x000000FF), (int)(pixel & 0x0000FF00) >> 8, (int)(pixel & 0x00FF0000) >> 16);
return color;
}
public static void Main()
{

Console.ReadKey ();
}
}

请帮我写全这段代码，我自己写了N久，还是没搞清楚怎么用这个函数

Answer 1

//我给你加个注释吧
//获取屏幕指定点的颜色
public Color GetColor(int x, int y)
{
int hdc = GetDC(IntPtr .Zero ); //获取屏幕HDC句柄
uint pixel = GetPixel(hdc, x, y); //获取屏幕上（x，y）点的颜色值,这个值是一个32位无符号整数。
ReleaseDC(IntPtr.Zero, hdc); //释放HDC句柄
//Color.FromArgb(red颜色分量,green颜色分量,blue颜色分量)
//pixel & 0x000000FF取低8位red色颜色分量
//(pixel & 0x0000FF00) >> 8 去8-16为green颜色分量,并且右移8位
//其他类似
Color color = Color.FromArgb((int)(pixel & 0x000000FF), (int)(pixel & 0x0000FF00) >> 8, (int)(pixel & 0x00FF0000) >> 16);
return color;
}

Answer 2

有必要这么复杂么

var bmp = new Bitmap(你的屏幕尺寸，可以从Screen类获取);
var g = Graphics.FromImage(bmp);
g.CopyFromScreen(你的屏幕尺寸)
bmp有获取像素点的方法

Answer 3

var bmp = new Bitmap(你的屏幕尺寸，可以从Screen类获取);
var g = Graphics.FromImage(bmp);
g.CopyFromScreen(你的屏幕尺寸)
bmp有获取像素点的方法