如何在图片框中进行自由格式选择（如在paint或photoshop中），然后裁剪该选项并将其保存到文件夹中？ 我已经做了一个矩形裁剪，但我想要那个自由形式的选择..
这是我的矩形裁剪：
Image img;
bool mouseClicked;
Point startPoint = new Point();
Point endPoint = new Point();
Rectangle rectCropArea;
private void Button1_Click(System.Object sender, System.EventArgs e)
{
}
private void OnLoad(System.Object sender, System.EventArgs e)
{
loadPrimaryImage();
}
private void loadPrimaryImage()
{
img = Image.FromFile("..\\..\\images.jpg");
PictureBox1.Image = img;
}
private void PicBox_MouseUp(System.Object sender, System.Windows.Forms.MouseEventArgs e)
{
mouseClicked = false;
if ((endPoint.X != -1)) {
Point currentPoint = new Point(e.X, e.Y);
Y1.Text = e.X.ToString();
Y2.Text = e.Y.ToString();
}
endPoint.X = -1;
endPoint.Y = -1;
startPoint.X = -1;
startPoint.Y = -1;
}
private void PicBox_MouseDown(System.Object sender, System.Windows.Forms.MouseEventArgs e)
{
mouseClicked = true;
startPoint.X = e.X;
startPoint.Y = e.Y;
//Display coordinates
X1.Text = startPoint.X.ToString();
Y1.Text = startPoint.Y.ToString();
endPoint.X = -1;
endPoint.Y = -1;
rectCropArea = new Rectangle(new Point(e.X, e.Y), new Size());
}
private void PicBox_MouseMove(System.Object sender, System.Windows.Forms.MouseEventArgs e)
{
Point ptCurrent = new Point(e.X, e.Y);
if ((mouseClicked)) {
if ((endPoint.X != -1)) {
//Display Coordinates
X1.Text = startPoint.X.ToString();
Y1.Text = startPoint.Y.ToString();
X2.Text = e.X.ToString();
Y2.Text = e.Y.ToString();
}
endPoint = ptCurrent;
if ((e.X > startPoint.X & e.Y > startPoint.Y)) {
rectCropArea.Width = e.X - startPoint.X;
rectCropArea.Height = e.Y - startPoint.Y;
} else if ((e.X < startPoint.X & e.Y > startPoint.Y)) {
rectCropArea.Width = startPoint.X - e.X;
rectCropArea.Height = e.Y - startPoint.Y;
rectCropArea.X = e.X;
rectCropArea.Y = startPoint.Y;
} else if ((e.X > startPoint.X & e.Y < startPoint.Y)) {
rectCropArea.Width = e.X - startPoint.X;
rectCropArea.Height = startPoint.Y - e.Y;
rectCropArea.X = startPoint.X;
rectCropArea.Y = e.Y;
} else {
rectCropArea.Width = startPoint.X - e.X;
rectCropArea.Height = startPoint.Y - e.Y;
rectCropArea.X = e.X;
rectCropArea.Y = e.Y;
}
PictureBox1.Refresh();
}
}
private void PicBox_Paint(System.Object sender, System.Windows.Forms.PaintEventArgs e)
{
Pen drawLine = new Pen(Color.Red);
drawLine.DashStyle = DashStyle.Dash;
e.Graphics.DrawRectangle(drawLine, rectCropArea);
}
private void btnCrop_Click(System.Object sender, System.EventArgs e)
{
PictureBox2.Refresh();
Bitmap sourceBitmap = new Bitmap(PictureBox1.Image, PictureBox1.Width, PictureBox1.Height);
Graphics g = PictureBox2.CreateGraphics();
if (!(CheckBox1.Checked)) {
g.DrawImage(sourceBitmap, new Rectangle(0, 0, PictureBox2.Width, PictureBox2.Height), rectCropArea, GraphicsUnit.Pixel);
sourceBitmap.Dispose();
} else {
int x1 = 0;
int x2 = 0;
int y1 = 0;
int y2 = 0;
try {
x1 = Convert.ToInt32(CX1.Text);
x2 = Convert.ToInt32(CX2.Text);
y1 = Convert.ToInt32(CY1.Text);
y2 = Convert.ToInt32(CY2.Text);
} catch (Exception ex) {
MessageBox.Show("Enter valid Coordinates (only Integer values)");
}
if (((x1 < x2 & y1 < y2))) {
rectCropArea = new Rectangle(x1, y1, x2 - x1, y2 - y1);
} else if ((x2 < x1 & y2 > y1)) {
rectCropArea = new Rectangle(x2, y1, x1 - x2, y2 - y1);
} else if ((x2 > x1 & y2 < y1)) {
rectCropArea = new Rectangle(x1, y2, x2 - x1, y1 - y2);
} else {
rectCropArea = new Rectangle(x2, y2, x1 - x2, y1 - y2);
}
PictureBox1.Refresh();
//This repositions the dashed box to new location as per coordinates entered.
g.DrawImage(sourceBitmap, new Rectangle(0, 0, PictureBox2.Width, PictureBox2.Height), rectCropArea, GraphicsUnit.Pixel);
sourceBitmap.Dispose();
}
}
private void pictureBox1_MouseClick(System.Object sender, System.Windows.Forms.MouseEventArgs e)
{
PictureBox1.Refresh();
}
private void CheckBox1_CheckedChanged(System.Object sender, System.EventArgs e)
{
if ((CheckBox1.Checked)) {
CX1.Visible = true;
Label10.Visible = true;
CY1.Visible = true;
Label9.Visible = true;
CX2.Visible = true;
Label8.Visible = true;
CY2.Visible = true;
Label7.Visible = true;
X1.Text = "0";
X2.Text = "0";
Y1.Text = "0";
Y2.Text = "0";
} else {
CX1.Visible = false;
Label10.Visible = false;
CY1.Visible = false;
Label9.Visible = false;
CX2.Visible = false;
Label8.Visible = false;
CY2.Visible = false;
Label7.Visible = false;
}
}
public Form1()
{
Load += OnLoad;
}
}
答案 0 :(得分：0)
要复制自由格式选择，您需要使用多边形。
这是一个完整的例子。只需将其粘贴到一个新的解决方案中并尝试一下（只需更改图像的路径）。 它将创建2个图片框并将图像加载到第一个图片框中并创建图像。然后你可以点击第一张图片，当你点击2次后它会开始显示一个选择，当你完成后只需按下按钮，它就会将选择复制到另一个图片框，然后将其保存为png图像。
它的作用是从第一个图像创建一个画笔，然后将多边形绘制到另一个图像上，并将矩形中的其他像素设置为您选择的背景颜色，在本例中为颜色：Color.Transparent。 / p>
示例：
public partial class Form1 : Form {
private List<Point> _points = new List<Point>();
private PictureBox _pictureBox1;
private PictureBox _pictureBox2;
private Button _button1;
public Form1() {
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e) {
Size = new Size(1366, 675);
_pictureBox1 = new PictureBox {
Location = new Point(12, 51),
Size = new Size(651, 474),
BorderStyle = BorderStyle.FixedSingle
};
_pictureBox2 = new PictureBox
{
Location = new Point(669, 51),
Size = new Size(651, 474),
BorderStyle = BorderStyle.FixedSingle
};
_button1 = new Button {
Text = @"Copy selected area",
Location = new Point(13, 13),
Size = new Size(175, 23)
};
Controls.AddRange(new Control[] { _pictureBox1, _pictureBox2, _button1 });
_pictureBox1.Image = Image.FromFile(@"d:\temp\Hopetoun_falls.jpg");
_points = new List<Point>();
_pictureBox1.MouseDown += delegate(object o, MouseEventArgs args) { _points.Add(args.Location); _pictureBox1.Refresh(); };
_pictureBox1.Paint += pictureBox1_Paint;
_button1.Click += button_Click;
}
private void pictureBox1_Paint(object sender, PaintEventArgs e) {
if (_points.Count < 2) {
return;
}
var max = _points.Count;
for (int i = 1; i < max; i++) {
e.Graphics.DrawLine(Pens.Red, _points[i-1].X, _points[i-1].Y, _points[i].X, _points[i].Y);
}
e.Graphics.DrawLine(Pens.Red, _points[max - 1].X, _points[max - 1].Y, _points[0].X, _points[0].Y);
}
private static Bitmap GetSelectedArea(Image source, Color bgColor, List<Point> points) {
var bigBm = new Bitmap(source);
using (var gr = Graphics.FromImage(bigBm)) {
// Set the background color.
gr.Clear(bgColor);
// Make a brush out of the original image.
using (var br = new TextureBrush(source)) {
// Fill the selected area with the brush.
gr.FillPolygon(br, points.ToArray());
// Find the bounds of the selected area.
var sourceRect = GetPointListBounds(points);
// Make a bitmap that only holds the selected area.
var result = new Bitmap(sourceRect.Width, sourceRect.Height);
// Copy the selected area to the result bitmap.
using (var resultGr = Graphics.FromImage(result)) {
var destRect = new Rectangle(0, 0, sourceRect.Width, sourceRect.Height);
resultGr.DrawImage(bigBm, destRect, sourceRect, GraphicsUnit.Pixel);
}
// Return the result.
return result;
}
}
}
private static Rectangle GetPointListBounds(List<Point> points) {
int xmin = points[0].X;
int xmax = xmin;
int ymin = points[0].Y;
int ymax = ymin;
for (int i = 1; i < points.Count; i++) {
if (xmin > points[i].X) xmin = points[i].X;
if (xmax < points[i].X) xmax = points[i].X;
if (ymin > points[i].Y) ymin = points[i].Y;
if (ymax < points[i].Y) ymax = points[i].Y;
}
return new Rectangle(xmin, ymin, xmax - xmin, ymax - ymin);
}
private void button_Click(object sender, EventArgs e) {
if (_points.Count < 3) {
return;
}
var img = GetSelectedArea(_pictureBox1.Image, Color.Transparent, _points);
_pictureBox2.Image = img;
_pictureBox2.Image.Save(@"d:\temp\sample.png", ImageFormat.Png);
}
}