本文实例讲述了C#自定义签名章实现方法。分享给大家供大家参考。具体实现方法如下：
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Drawing;
using System.Drawing.Imaging;
using System.Drawing.Drawing2D;
namespace WfpApp
{
public class DrawCachet
{
/// <summary>
/// 自定义椭圆形签名章
/// </summary>
/// <param name="Width">宽度，画出的签名章只有这宽度的一半</param>
/// <param name="Height">高度，画出的签名章只有这高度的一半</param>
/// <param name="test">签名章上名字</param>
/// <param name="IsRotate">签名章是否旋转角度</param>
/// <param name="angle">旋转角度的大小</param>
/// <returns></returns>
public static Bitmap GetDrawCircleCachet( int Width, int Height, string test, bool IsRotate, int angle)
{
//记录圆画笔的粗细
int Circle_Brush = 2;
//画布
Bitmap bitmap = new Bitmap(Width, Height);
//定义字符串的样式
Font var_Font = new Font( "Arial" , 13, FontStyle.Bold);
//定义一个矩形 ,设置圆的绘制区
Rectangle rect = new Rectangle(10, 10, Width / 2, Height / 2);
//实例化Graphic类
Graphics g = System.Drawing.Graphics.FromImage(bitmap);
//消除绘制图形的锯齿，平滑
g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.AntiAlias;
//以白色清空panelCachet画布背景
g.Clear(Color.White);
//设置画笔的颜色
Pen mypen = new Pen(Color.Red, Circle_Brush);
//绘制圆
g.DrawEllipse(mypen, rect);
//设置文字的字体样式
Font star_Font = new Font( "Arial" , 12, FontStyle.Regular);
//对字符串进行宽度和长度测量
SizeF var_Size = g.MeasureString(test, star_Font);
float CircleZjW = rect.Width + 2 * Circle_Brush;
float CircleZJH = rect.Height + 2 * Circle_Brush;
float x = (CircleZjW - var_Size.Width) / 2F + rect.X;
float y = (CircleZJH - var_Size.Height) / 2F + rect.Y;
//在指定的位置绘制文字
g.DrawString(test, star_Font, mypen.Brush, new PointF(x, y));
if (IsRotate)
bitmap = Rotate(bitmap, angle);
return bitmap;
}
/// <summary>
/// 自定义矩形签名章
/// </summary>
/// <param name="width">宽度，画出的签名章只有这宽度的一半</param>
/// <param name="height">高度，画出的签名章只有这高度的一半</param>
/// <param name="name">签名章上名字</param>
/// <param name="IsRotate">签名章是否旋转角度</param>
/// <param name="angle">旋转角度的大小</param>
/// <returns></returns>
public static Bitmap GetDrawRectangle( int width, int height, string name, bool IsRotate, int angle)
{
//记录圆画笔的粗细
int Circle_Brush = 2;
//画布
Bitmap bitmap = new Bitmap(width, height);
//定义字符串的样式
Font var_Font = new Font( "Arial" , 13, FontStyle.Bold);
//定义一个矩形 ,设置圆的绘制区
Rectangle rect = new Rectangle(10, 10, width / 2, height / 2);
//实例化Graphic类
Graphics g = System.Drawing.Graphics.FromImage(bitmap);
//消除绘制图形的锯齿，平滑
g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.AntiAlias;
//以白色清空panelCachet画布背景
g.Clear(Color.White);
//设置画笔的颜色
Pen mypen = new Pen(Color.Red, Circle_Brush);
//绘制圆
g.DrawRectangle(mypen, rect);
//设置文字的字体样式
Font star_Font = new Font( "Arial" , 12, FontStyle.Regular);
//对字符串进行宽度和长度测量
SizeF var_Size = g.MeasureString(name, star_Font);
float CircleZjW = rect.Width + 2 * Circle_Brush;
float CircleZJH = rect.Height + 2 * Circle_Brush;
float x = (CircleZjW - var_Size.Width) / 2F + rect.X;
float y = (CircleZJH - var_Size.Height) / 2F + rect.Y;
//在指定的位置绘制文字
g.DrawString(name, star_Font, mypen.Brush, new PointF(x, y));
if (IsRotate)
bitmap = Rotate(bitmap, angle);
return bitmap;
}
/// <summary>
/// 签名章旋转
/// </summary>
/// <param name="b">Bitmap图章</param>
/// <param name="angle">旋转度</param>
/// <returns></returns>
static Bitmap Rotate(Bitmap b, int angle)
{
angle = angle % 360;
//弧度转换
double radian = angle * Math.PI / 180.0;
double cos = Math.Cos(radian);
double sin = Math.Sin(radian);
//原图的宽和高
int w = b.Width;
int h = b.Height;
int W = ( int )(Math.Max(Math.Abs(w * cos - h * sin), Math.Abs(w * cos + h * sin)));
int H = ( int )(Math.Max(Math.Abs(w * sin - h * cos), Math.Abs(w * sin + h * cos)));
//目标位图
Bitmap dsImage = new Bitmap(W, H);
System.Drawing.Graphics g = System.Drawing.Graphics.FromImage(dsImage);
g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.Bilinear;
g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;
//计算偏移量
Point Offset = new Point((W - w) / 2, (H - h) / 2);
//构造图像显示区域：让图像的中心与窗口的中心点一致
Rectangle rect = new Rectangle(Offset.X, Offset.Y, w, h);
Point center = new Point(rect.X + rect.Width / 2, rect.Y + rect.Height / 2);
g.TranslateTransform(center.X, center.Y);
g.RotateTransform(360 - angle);
//恢复图像在水平和垂直方向的平移
g.TranslateTransform(-center.X, -center.Y);
g.DrawImage(b, rect);
//重至绘图的所有变换
g.ResetTransform();
g.Save();
g.Dispose();
//dsImage.Save("yuancd.jpg", System.Drawing.Imaging.ImageFormat.Jpeg);
return dsImage;
}
}
}
希望本文所述对大家的C#程序设计有所帮助。
dy("nrwz");