using System;
using System.Collections.Generic;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Drawing.Imaging;
using System.Linq;
using System.Text;
namespace NopSolutions.NopCommerce.Controls{
/// <summary>
/// Capture helper class
/// </summary>
public partial class Captcha
{
private string text;
private int width;
private int height;
private string familyName;
private Bitmap image;
private Random random = new Random();
/// <summary>
/// Initializes a new instance of the CaptchaImage class using the specified text, width and height.
/// </summary>
/// <param name="s">Text</param>
/// <param name="width">Width</param>
/// <param name="height">Height</param>
public Captcha(string s, int width, int height)
{
this.text = s;
this.SetDimensions(width, height);
this.GenerateImage();
}
/// <summary>
/// Initializes a new instance of the CaptchaImage class using the specified text, width, height and font family.
/// </summary>
/// <param name="s">Text</param>
/// <param name="width">Width</param>
/// <param name="height">Height</param>
/// <param name="familyName">Font family</param>
public Captcha(string s, int width, int height, string familyName)
{
this.text = s;
this.SetDimensions(width, height);
this.SetFamilyName(familyName);
this.GenerateImage();
}
/// <summary>
/// This member overrides Object.Finalize.
/// </summary>
~Captcha()
{
Dispose(false);
}
/// <summary>
/// Releases all resources used by this object.
/// </summary>
public void Dispose()
{
GC.SuppressFinalize(this);
this.Dispose(true);
}
/// <summary>
/// Custom Dispose method to clean up unmanaged resources.
/// </summary>
/// <param name="disposing">Disposing flag</param>
protected virtual void Dispose(bool disposing)
{
if (disposing)
// Dispose of the bitmap.
this.image.Dispose();
}
/// <summary>
/// Sets the image width and height.
/// </summary>
/// <param name="width">Width</param>
/// <param name="height">Height</param>
private void SetDimensions(int width, int height)
{
// Check the width and height.
if (width <= 0)
throw new ArgumentOutOfRangeException("width", width, "Argument out of range, must be greater than zero.");
if (height <= 0)
throw new ArgumentOutOfRangeException("height", height, "Argument out of range, must be greater than zero.");
this.width = width;
this.height = height;
}
/// <summary>
/// Sets the font used for the image text.
/// </summary>
/// <param name="familyName">Font family</param>
private void SetFamilyName(string familyName)
{
// If the named font is not installed, default to a system font.
try
{
Font font = new Font(this.familyName, 12F);
this.familyName = familyName;
font.Dispose();
}
catch
{
this.familyName = System.Drawing.FontFamily.GenericSerif.Name;
}
}
/// <summary>
/// Creates the bitmap image.
/// </summary>
private void GenerateImage()
{
// Create a new 32-bit bitmap image.
Bitmap bitmap = new Bitmap(this.width, this.height, PixelFormat.Format32bppArgb);
// Create a graphics object for drawing.
Graphics g = Graphics.FromImage(bitmap);
g.SmoothingMode = SmoothingMode.AntiAlias;
Rectangle rect = new Rectangle(0, 0, this.width, this.height);
// Fill in the background.
var hatchBrush = new HatchBrush(HatchStyle.SmallConfetti, Color.LightGray, Color.White);
g.FillRectangle(hatchBrush, rect);
// Set up the text font.
SizeF size;
float fontSize = rect.Height + 1;
Font font;
// Adjust the font size until the text fits within the image.
do
{
fontSize--;
font = new Font(this.familyName, fontSize, FontStyle.Bold);
size = g.MeasureString(this.text, font);
} while (size.Width > rect.Width);
// Set up the text format.
var format = new StringFormat();
format.Alignment = StringAlignment.Center;
format.LineAlignment = StringAlignment.Center;
// Create a path using the text and warp it randomly.
var path = new GraphicsPath();
path.AddString(this.text, font.FontFamily, (int)font.Style, font.Size, rect, format);
float v = 4F;
PointF[] points =
{
new PointF(this.random.Next(rect.Width) / v, this.random.Next(rect.Height) / v),
new PointF(rect.Width - this.random.Next(rect.Width) / v, this.random.Next(rect.Height) / v),
new PointF(this.random.Next(rect.Width) / v, rect.Height - this.random.Next(rect.Height) / v),
new PointF(rect.Width - this.random.Next(rect.Width) / v, rect.Height - this.random.Next(rect.Height) / v)
};
var matrix = new Matrix();
matrix.Translate(0F, 0F);
path.Warp(points, rect, matrix, WarpMode.Perspective, 0F);
// Draw the text.
hatchBrush = new HatchBrush(HatchStyle.LargeConfetti, Color.LightGray, Color.DarkGray);
g.FillPath(hatchBrush, path);
// Add some random noise.
int m = Math.Max(rect.Width, rect.Height);
for (int i = 0; i < (int)(rect.Width * rect.Height / 30F); i++)
{
int x = this.random.Next(rect.Width);
int y = this.random.Next(rect.Height);
int w = this.random.Next(m / 50);
int h = this.random.Next(m / 50);
g.FillEllipse(hatchBrush, x, y, w, h);
}
// Clean up.
font.Dispose();
hatchBrush.Dispose();
g.Dispose();
// Set the image.
this.image = bitmap;
}
/// <summary>
/// Text
/// </summary>
public string Text
{
get { return this.text; }
}
/// <summary>
/// Image
/// </summary>
public Bitmap Image
{
get { return this.image; }
}
/// <summary>
/// Width
/// </summary>
public int Width
{
get { return this.width; }
}
/// <summary>
/// Height
/// </summary>
public int Height
{
get { return this.height; }
}
}
}
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