本文实例讲述了C#绘制曲线图的方法。分享给大家供大家参考。具体如下：

1. 曲线图效果：

2. C#代码：

/// <summary>/// 自动根据参数调整图像大小/// </summary>public void Fit(){ //计算字体距离 intFontSpace = FontSize + 5; //计算图像边距 float fltSpace = Math.Min(Width / 6, Height / 6); XSpace = fltSpace; YSpace = fltSpace; //计算X轴刻度宽度 XSlice = (Width - 2 * XSpace) / (Keys.Length - 1); //计算Y轴刻度宽度和Y轴刻度开始值 float fltMinValue = 0; float fltMaxValue = 0; for (int i = 0; i < Values.Length; i++) { if (Values[i] < fltMinValue) { fltMinValue = Values[i]; } else if (Values[i] > fltMaxValue) { fltMaxValue = Values[i]; } } if (YSliceBegin > fltMinValue) { YSliceBegin = fltMinValue; } int intYSliceCount = (int)(fltMaxValue / YSliceValue); if (fltMaxValue % YSliceValue != 0) { intYSliceCount++; } YSlice = (Height - 2 * YSpace) / intYSliceCount;}

3. 数据缩小一个级别的效果：

4. 完整代码 DrawingCurve.cs：

using System;using System.Collections.Generic;using System.Text;using System.Drawing;using System.Data;using System.Drawing.Drawing2D;namespace SarchPMS.Business.Draw{ public class DrawingCurve : DrawingChart { /// <summary> /// 画曲线图 /// </summary> /// <param name="dsParameter"></param> /// <returns></returns> public override Bitmap DrawImage(DataSet dsParameter) { Curve2D cuv2D = new Curve2D(); cuv2D.Fit(); return cuv2D.CreateImage(); } } public class Curve2D { private Graphics objGraphics; //Graphics 类提供将对象绘制到显示设备的方法 private Bitmap objBitmap; //位图对象 private float fltWidth = 480; //图像宽度 private float fltHeight = 248; //图像高度 private float fltXSlice = 50; //X轴刻度宽度 private float fltYSlice = 50; //Y轴刻度宽度 private float fltYSliceValue = 20; //Y轴刻度的数值宽度 private float fltYSliceBegin = 0; //Y轴刻度开始值 private float fltTension = 0.5f; private string strTitle = "曲线图"; //标题 private string strXAxisText = "月份"; //X轴说明文字 private string strYAxisText = "万元"; //Y轴说明文字 private string[] strsKeys = new string[] { "一月", "二月", "三月", "四月", "五月", "六月", "七月", "八月", "九月", "十月", "十一月", "十二月" }; //键 private float[] fltsValues = new float[] { 20.0f, 30.0f, 50.0f, 55.4f, 21.6f, 12.8f, 99.5f, 36.4f, 78.2f, 56.4f, 45.8f, 66.5f, 99.5f, 36.4f, 78.2f, 56.4f, 45.8f, 66.5f, 20.0f, 30.0f, 50.0f, 55.4f, 21.6f, 12.8f }; //值 private Color clrBgColor = Color.Snow; //背景色 private Color clrTextColor = Color.Black; //文字颜色 private Color clrBorderColor = Color.Black; //整体边框颜色 private Color clrAxisColor = Color.Black; //轴线颜色 private Color clrAxisTextColor = Color.Black; //轴说明文字颜色 private Color clrSliceTextColor = Color.Black; //刻度文字颜色 private Color clrSliceColor = Color.Black; //刻度颜色 private Color[] clrsCurveColors = new Color[] { Color.Red, Color.Blue }; //曲线颜色 private float fltXSpace = 100f; //图像左右距离边缘距离 private float fltYSpace = 100f; //图像上下距离边缘距离 private int intFontSize = 9; //字体大小号数 private float fltXRotateAngle = 30f; //X轴文字旋转角度 private float fltYRotateAngle = 0f; //Y轴文字旋转角度 private int intCurveSize = 2; //曲线线条大小 private int intFontSpace = 0; //intFontSpace 是字体大小和距离调整出来的一个比较适合的数字 #region 公共属性 /// <summary> /// 图像的宽度 /// </summary> public float Width { set { if (value < 100) { fltWidth = 100; } else { fltWidth = value; } } get { if (fltWidth <= 100) { return 100; } else { return fltWidth; } } } /// <summary> /// 图像的高度 /// </summary> public float Height { set { if (value < 100) { fltHeight = 100; } else { fltHeight = value; } } get { if (fltHeight <= 100) { return 100; } else { return fltHeight; } } } /// <summary> /// X轴刻度宽度 /// </summary> public float XSlice { set { fltXSlice = value; } get { return fltXSlice; } } /// <summary> /// Y轴刻度宽度 /// </summary> public float YSlice { set { fltYSlice = value; } get { return fltYSlice; } } /// <summary> /// Y轴刻度的数值宽度 /// </summary> public float YSliceValue { set { fltYSliceValue = value; } get { return fltYSliceValue; } } /// <summary> /// Y轴刻度开始值 /// </summary> public float YSliceBegin { set { fltYSliceBegin = value; } get { return fltYSliceBegin; } } /// <summary> /// 张力系数 /// </summary> public float Tension { set { if (value < 0.0f && value > 1.0f) { fltTension = 0.5f; } else { fltTension = value; } } get { return fltTension; } } /// <summary> /// 标题 /// </summary> public string Title { set { strTitle = value; } get { return strTitle; } } /// <summary> /// 键，X轴数据 /// </summary> public string[] Keys { set { strsKeys = value; } get { return strsKeys; } } /// <summary> /// 值，Y轴数据 /// </summary> public float[] Values { set { fltsValues = value; } get { return fltsValues; } } /// <summary> /// 背景色 /// </summary> public Color BgColor { set { clrBgColor = value; } get { return clrBgColor; } } /// <summary> /// 文字颜色 /// </summary> public Color TextColor { set { clrTextColor = value; } get { return clrTextColor; } } /// <summary> /// 整体边框颜色 /// </summary> public Color BorderColor { set { clrBorderColor = value; } get { return clrBorderColor; } } /// <summary> /// 轴线颜色 /// </summary> public Color AxisColor { set { clrAxisColor = value; } get { return clrAxisColor; } } /// <summary> /// X轴说明文字 /// </summary> public string XAxisText { set { strXAxisText = value; } get { return strXAxisText; } } /// <summary> /// Y轴说明文字 /// </summary> public string YAxisText { set { strYAxisText = value; } get { return strYAxisText; } } /// <summary> /// 轴说明文字颜色 /// </summary> public Color AxisTextColor { set { clrAxisTextColor = value; } get { return clrAxisTextColor; } } /// <summary> /// 刻度文字颜色 /// </summary> public Color SliceTextColor { set { clrSliceTextColor = value; } get { return clrSliceTextColor; } } /// <summary> /// 刻度颜色 /// </summary> public Color SliceColor { set { clrSliceColor = value; } get { return clrSliceColor; } } /// <summary> /// 曲线颜色 /// </summary> public Color[] CurveColors { set { clrsCurveColors = value; } get { return clrsCurveColors; } } /// <summary> /// X轴文字旋转角度 /// </summary> public float XRotateAngle { get { return fltXRotateAngle; } set { fltXRotateAngle = value; } } /// <summary> /// Y轴文字旋转角度 /// </summary> public float YRotateAngle { get { return fltYRotateAngle; } set { fltYRotateAngle = value; } } /// <summary> /// 图像左右距离边缘距离 /// </summary> public float XSpace { get { return fltXSpace; } set { fltXSpace = value; } } /// <summary> /// 图像上下距离边缘距离 /// </summary> public float YSpace { get { return fltYSpace; } set { fltYSpace = value; } } /// <summary> /// 字体大小号数 /// </summary> public int FontSize { get { return intFontSize; } set { intFontSize = value; } } /// <summary> /// 曲线线条大小 /// </summary> public int CurveSize { get { return intCurveSize; } set { intCurveSize = value; } } #endregion /// <summary> /// 自动根据参数调整图像大小 /// </summary> public void Fit() { //计算字体距离 intFontSpace = FontSize + 5; //计算图像边距 float fltSpace = Math.Min(Width / 6, Height / 6); XSpace = fltSpace; YSpace = fltSpace; //计算X轴刻度宽度 XSlice = (Width - 2 * XSpace) / (Keys.Length - 1); //计算Y轴刻度宽度和Y轴刻度开始值 float fltMinValue = 0; float fltMaxValue = 0; for (int i = 0; i < Values.Length; i++) { if (Values[i] < fltMinValue) { fltMinValue = Values[i]; } else if (Values[i] > fltMaxValue) { fltMaxValue = Values[i]; } } if (YSliceBegin > fltMinValue) { YSliceBegin = fltMinValue; } int intYSliceCount = (int)(fltMaxValue / YSliceValue); if (fltMaxValue % YSliceValue != 0) { intYSliceCount++; } YSlice = (Height - 2 * YSpace) / intYSliceCount; } /// <summary> /// 生成图像并返回bmp图像对象 /// </summary> /// <returns></returns> public Bitmap CreateImage() { InitializeGraph(); int intKeysCount = Keys.Length; int intValuesCount = Values.Length; if (intValuesCount % intKeysCount == 0) { int intCurvesCount = intValuesCount / intKeysCount; for (int i = 0; i < intCurvesCount; i++) { float[] fltCurrentValues = new float[intKeysCount]; for (int j = 0; j < intKeysCount; j++) { fltCurrentValues[j] = Values[i * intKeysCount + j]; } DrawContent(ref objGraphics, fltCurrentValues, clrsCurveColors[i]); } } else { objGraphics.DrawString("发生错误，Values的长度必须是Keys的整数倍!", new Font("宋体", FontSize + 5), new SolidBrush(TextColor), new Point((int)XSpace, (int)(Height / 2))); } return objBitmap; } /// <summary> /// 初始化和填充图像区域，画出边框，初始标题 /// </summary> private void InitializeGraph() { //根据给定的高度和宽度创建一个位图图像 objBitmap = new Bitmap((int)Width, (int)Height); //从指定的 objBitmap 对象创建 objGraphics 对象 (即在objBitmap对象中画图) objGraphics = Graphics.FromImage(objBitmap); //根据给定颜色(LightGray)填充图像的矩形区域 (背景) objGraphics.DrawRectangle(new Pen(BorderColor, 1), 0, 0, Width - 1, Height - 1); //画边框 objGraphics.FillRectangle(new SolidBrush(BgColor), 1, 1, Width - 2, Height - 2); //填充边框 //画X轴,注意图像的原始X轴和Y轴计算是以左上角为原点，向右和向下计算的 float fltX1 = XSpace; float fltY1 = Height - YSpace; float fltX2 = Width - XSpace + XSlice / 2; float fltY2 = fltY1; objGraphics.DrawLine(new Pen(new SolidBrush(AxisColor), 1), fltX1, fltY1, fltX2, fltY2); //画Y轴 fltX1 = XSpace; fltY1 = Height - YSpace; fltX2 = XSpace; fltY2 = YSpace - YSlice / 2; objGraphics.DrawLine(new Pen(new SolidBrush(AxisColor), 1), fltX1, fltY1, fltX2, fltY2); //初始化轴线说明文字 SetAxisText(ref objGraphics); //初始化X轴上的刻度和文字 SetXAxis(ref objGraphics); //初始化Y轴上的刻度和文字 SetYAxis(ref objGraphics); //初始化标题 CreateTitle(ref objGraphics); } /// <summary> /// 初始化轴线说明文字 /// </summary> /// <param name="objGraphics"></param> private void SetAxisText(ref Graphics objGraphics) { float fltX = Width - XSpace + XSlice / 2 - (XAxisText.Length - 1) * intFontSpace; float fltY = Height - YSpace - intFontSpace; objGraphics.DrawString(XAxisText, new Font("宋体", FontSize), new SolidBrush(AxisTextColor), fltX, fltY); fltX = XSpace + 5; fltY = YSpace - YSlice / 2 - intFontSpace; for (int i = 0; i < YAxisText.Length; i++) { objGraphics.DrawString(YAxisText[i].ToString(), new Font("宋体", FontSize), new SolidBrush(AxisTextColor), fltX, fltY); fltY += intFontSpace; //字体上下距离 } } /// <summary> /// 初始化X轴上的刻度和文字 /// </summary> /// <param name="objGraphics"></param> private void SetXAxis(ref Graphics objGraphics) { float fltX1 = XSpace; float fltY1 = Height - YSpace; float fltX2 = XSpace; float fltY2 = Height - YSpace; int iCount = 0; int iSliceCount = 1; float Scale = 0; float iWidth = ((Width - 2 * XSpace) / XSlice) * 50; //将要画刻度的长度分段，并乘以50，以10为单位画刻度线。 float fltSliceHeight = XSlice / 10; //刻度线的高度 objGraphics.TranslateTransform(fltX1, fltY1); //平移图像(原点) objGraphics.RotateTransform(XRotateAngle, MatrixOrder.Prepend); //旋转图像 objGraphics.DrawString(Keys[0].ToString(), new Font("宋体", FontSize), new SolidBrush(SliceTextColor), 0, 0); objGraphics.ResetTransform(); //重置图像 for (int i = 0; i <= iWidth; i += 10) //以10为单位 { Scale = i * XSlice / 50;//即(i / 10) * (XSlice / 5)，将每个刻度分五部分画，但因为i以10为单位，得除以10 if (iCount == 5) { objGraphics.DrawLine(new Pen(new SolidBrush(AxisColor)), fltX1 + Scale, fltY1 + fltSliceHeight * 1.5f, fltX2 + Scale, fltY2 - fltSliceHeight * 1.5f); //画网格虚线 Pen penDashed = new Pen(new SolidBrush(AxisColor)); penDashed.DashStyle = DashStyle.Dash; objGraphics.DrawLine(penDashed, fltX1 + Scale, fltY1, fltX2 + Scale, YSpace - YSlice / 2); //这里显示X轴刻度 if (iSliceCount <= Keys.Length - 1) { objGraphics.TranslateTransform(fltX1 + Scale, fltY1); objGraphics.RotateTransform(XRotateAngle, MatrixOrder.Prepend); objGraphics.DrawString(Keys[iSliceCount].ToString(), new Font("宋体", FontSize), new SolidBrush(SliceTextColor), 0, 0); objGraphics.ResetTransform(); } else { //超过范围，不画任何刻度文字 } iCount = 0; iSliceCount++; if (fltX1 + Scale > Width - XSpace) { break; } } else { objGraphics.DrawLine(new Pen(new SolidBrush(SliceColor)), fltX1 + Scale, fltY1 + fltSliceHeight, fltX2 + Scale, fltY2 - fltSliceHeight); } iCount++; } } /// <summary> /// 初始化Y轴上的刻度和文字 /// </summary> /// <param name="objGraphics"></param> private void SetYAxis(ref Graphics objGraphics) { float fltX1 = XSpace; float fltY1 = Height - YSpace; float fltX2 = XSpace; float fltY2 = Height - YSpace; int iCount = 0; float Scale = 0; int iSliceCount = 1; float iHeight = ((Height - 2 * YSpace) / YSlice) * 50; //将要画刻度的长度分段，并乘以50，以10为单位画刻度线。 float fltSliceWidth = YSlice / 10; //刻度线的宽度 string strSliceText = string.Empty; objGraphics.TranslateTransform(XSpace - intFontSpace * YSliceBegin.ToString().Length, Height - YSpace); //平移图像(原点) objGraphics.RotateTransform(YRotateAngle, MatrixOrder.Prepend); //旋转图像 objGraphics.DrawString(YSliceBegin.ToString(), new Font("宋体", FontSize), new SolidBrush(SliceTextColor), 0, 0); objGraphics.ResetTransform(); //重置图像 for (int i = 0; i < iHeight; i += 10) { Scale = i * YSlice / 50; //即(i / 10) * (YSlice / 5)，将每个刻度分五部分画，但因为i以10为单位，得除以10 if (iCount == 5) { objGraphics.DrawLine(new Pen(new SolidBrush(AxisColor)), fltX1 - fltSliceWidth * 1.5f, fltY1 - Scale, fltX2 + fltSliceWidth * 1.5f, fltY2 - Scale); //画网格虚线 Pen penDashed = new Pen(new SolidBrush(AxisColor)); penDashed.DashStyle = DashStyle.Dash; objGraphics.DrawLine(penDashed, XSpace, fltY1 - Scale, Width - XSpace + XSlice / 2, fltY2 - Scale); //这里显示Y轴刻度 strSliceText = Convert.ToString(YSliceValue * iSliceCount + YSliceBegin); objGraphics.TranslateTransform(XSpace - intFontSize * strSliceText.Length, fltY1 - Scale); //平移图像(原点) objGraphics.RotateTransform(YRotateAngle, MatrixOrder.Prepend); //旋转图像 objGraphics.DrawString(strSliceText, new Font("宋体", FontSize), new SolidBrush(SliceTextColor), 0, 0); objGraphics.ResetTransform(); //重置图像 iCount = 0; iSliceCount++; } else { objGraphics.DrawLine(new Pen(new SolidBrush(SliceColor)), fltX1 - fltSliceWidth, fltY1 - Scale, fltX2 + fltSliceWidth, fltY2 - Scale); } iCount++; } } /// <summary> /// 画曲线 /// </summary> /// <param name="objGraphics"></param> private void DrawContent(ref Graphics objGraphics, float[] fltCurrentValues, Color clrCurrentColor) { Pen CurvePen = new Pen(clrCurrentColor, CurveSize); PointF[] CurvePointF = new PointF[Keys.Length]; float keys = 0; float values = 0; for (int i = 0; i < Keys.Length; i++) { keys = XSlice * i + XSpace; values = (Height - YSpace) + YSliceBegin - YSlice * (fltCurrentValues[i] / YSliceValue); CurvePointF[i] = new PointF(keys, values); } objGraphics.DrawCurve(CurvePen, CurvePointF, Tension); } /// <summary> /// 初始化标题 /// </summary> /// <param name="objGraphics"></param> private void CreateTitle(ref Graphics objGraphics) { objGraphics.DrawString(Title, new Font("宋体", FontSize), new SolidBrush(TextColor), new Point((int)(Width - XSpace) - intFontSize * Title.Length, (int)(YSpace - YSlice / 2 - intFontSpace))); } }}

希望本文所述对大家的C#程序设计有所帮助。