如题，需求：在某个图片上用户可以手动指定位置。
如下：
中心思想：仿照Visual Studio工具中的控件的做法
如何仿照呢？
1.自定义的控件类继承System.Windows.Forms.Control
1.1.通过Graphics对象，绘制出我们想要的形状
1 #region enum 2 /// <summary> 3 /// 渐变颜色填充方向 4 /// </summary> 5 public enum LinearGradientDirection 6 { 7 /// <summary> 8 /// 垂直方向 9 /// </summary> 10 Vertical, 11 /// <summary> 12 /// 水平方向 13 /// </summary> 14 Horizontal 15 } 16 17 /// <summary> 18 /// 箭头方向 19 /// </summary> 20 public enum ArrowStyleType 21 { 22 /// <summary> 23 /// 没有箭头 24 /// </summary> 25 None, 26 /// <summary> 27 /// 左箭头（⬅） 28 /// </summary> 29 Left, 30 /// <summary> 31 /// 右箭头（➡） 32 /// </summary> 33 Right, 34 /// <summary> 35 /// 上箭头（↑） 36 /// </summary> 37 Top, 38 /// <summary> 39 /// 下箭头（⬇） 40 /// </summary> 41 Bottom, 42 /// <summary> 43 /// 左右箭头（↔） 44 /// </summary> 45 LeftRight, 46 /// <summary> 47 /// 上下箭头（↕） 48 /// </summary> 49 TopBottom, 50 /// <summary> 51 /// 上弓 52 /// </summary> 53 UpBow, 54 /// <summary> 55 /// 下弓 56 /// </summary> 57 DownBow, 58 /// <summary> 59 /// 左弓 60 /// </summary> 61 LeftBow, 62 /// <summary> 63 /// 右弓 64 /// </summary> 65 RightBow, 66 } 67 #endregion 68 69 class ArrowControll : System.Windows.Forms.Control 70 { 71 #region 变量 72 private PointF[] m_pnts = null; // 箭头点坐标 73 GraphicsPath m_gp = new GraphicsPath(); // 绘制路径 74 private Color m_ColorS = Color.WhiteSmoke; // 起始渐变色 75 private Color m_ColorE = Color.DarkGray; 76 private Color m_NormalStartColor = Color.WhiteSmoke; // 常规起始渐变色 77 private Color m_NormalEndColor = Color.DarkGray; 78 private LinearGradientDirection m_lgdirect = LinearGradientDirection.Horizontal; 79 private ArrowStyleType m_ArrowType = ArrowStyleType.UpBow; // 箭头类型 80 private float m_ArrowLength = 8.0f; // 箭标长度 81 private float m_ArrowBodyWidth = 8.0f; // 箭身宽度 82 83 private float m_BowHeight = 4.0f; // 弓长度 84 private float m_BowWidth = 4.0f; // 弓宽度 85 private bool m_antiAlias = false; // 反走样绘制 86 87 private bool m_FrameEnabled = false; 88 private int m_pCount = 8; 89 90 private const int MINSIZE = 2; // 最小大小 91 #endregion 92 93 #region 属性 94 /// <summary> 95 /// 开始渐变颜色 96 /// </summary> 97 public Color NormalStartColor 98 { 99 get { return m_NormalStartColor; } 100 set { m_NormalStartColor = value; Refresh(); } 101 } 102 103 /// <summary> 104 ///结束渐变颜色 105 /// </summary> 106 public Color NormalEndColor 107 { 108 get { return m_NormalEndColor; } 109 set { m_NormalEndColor = value; Refresh(); } 110 } 111 112 /// <summary> 113 /// 渐变色方向 114 /// </summary> 115 public LinearGradientDirection ColorLinearDirection 116 { 117 get { return m_lgdirect; } 118 set { m_lgdirect = value; Refresh(); } 119 } 120 121 /// <summary> 122 /// 是否有立体框架 123 /// </summary> 124 public bool FrameEnabled 125 { 126 get { return m_FrameEnabled; } 127 set { m_FrameEnabled = value; Refresh(); } 128 } 129 130 /// <summary> 131 /// 箭头类型 132 /// </summary> 133 public ArrowStyleType ArrowStyle 134 { 135 get { return m_ArrowType; } 136 set 137 { 138 m_ArrowType = value; 139 Clear(); 140 Init(); 141 Refresh(); 142 } 143 } 144 145 /// <summary> 146 /// 箭标长度 147 /// </summary> 148 public float ArrowLength 149 { 150 get { return m_ArrowLength; } 151 set 152 { 153 m_ArrowLength = value; 154 // AdjustmentBodyWH(); 155 Clear(); 156 Init(); 157 Refresh(); 158 } 159 } 160 161 /// <summary> 162 /// 箭身宽度 163 /// </summary> 164 public float ArrowBodyWidth 165 { 166 get { return m_ArrowBodyWidth; } 167 set 168 { 169 m_ArrowBodyWidth = value; 170 Clear(); 171 Init(); 172 Refresh(); 173 } 174 } 175 176 /// <summary> 177 /// 弓长度 178 /// </summary> 179 public float BowHeight 180 { 181 get { return m_BowHeight; } 182 set 183 { 184 m_BowHeight = value; 185 Clear(); 186 Init(); 187 Refresh(); 188 } 189 } 190 191 /// <summary> 192 /// 弓宽度 193 /// </summary> 194 public float BowWidth 195 { 196 get { return m_BowWidth; } 197 set 198 { 199 m_BowWidth = value; 200 Clear(); 201 Init(); 202 Refresh(); 203 } 204 } 205 206 /// <summary> 207 /// 反走样 208 /// </summary> 209 public bool AntiAlias 210 { 211 get { return m_antiAlias; } 212 set 213 { 214 m_antiAlias = value; 215 Clear(); 216 Init(); 217 Refresh(); 218 } 219 } 220 221 private bool m_LinearGradientUsingClient = true; //渐变色使用控件区域 222 /// <summary> 223 /// 渐变色使用是否只使用控件区域 224 /// </summary> 225 public bool LinearGradientUsingClient 226 { 227 get { return m_LinearGradientUsingClient; } 228 set 229 { 230 m_LinearGradientUsingClient = value; 231 { 232 Clear(); 233 Init(); 234 Refresh(); 235 } 236 } 237 } 238 239 private Rectangle m_LinearGradientRect; 240 /// <summary> 241 /// 渐变色使用区域范围 242 /// </summary> 243 public Rectangle LinearGradientRect 244 { 245 get { return m_LinearGradientRect; } 246 set 247 { 248 m_LinearGradientRect = value; 249 { 250 Clear(); 251 Init(); 252 Refresh(); 253 } 254 } 255 } 256 #endregion 257 258 #region 01构造函数 -- 箭头路径GraphicsPath m_gp = new GraphicsPath(); 259 /// <summary> 260 /// 通过构造函数 261 /// 绘制箭头路径 262 /// 初期化 263 /// </summary> 264 public ArrowControll() 265 { 266 InitializeComponent(); 267 Init(); 268 269 //在缓冲区中进行绘制，并且完成后将结果输出到屏幕。 270 //双缓冲可以防止因重绘控件而引起的闪烁。 271 //如果将 DoubleBuffer 设置为 true，则还应将 UserPaint 和 AllPaintingInWmPaint 设置为 true 272 SetStyle(ControlStyles.DoubleBuffer, true); 273 274 //控件忽略窗口消息 WM_ERASEBKGND 以减少闪烁。 275 //仅当将 UserPaint 位设置为 true 时，才应用此样式 276 SetStyle(ControlStyles.AllPaintingInWmPaint, true); 277 278 //如果为 true，则会由控件而不是由操作系统来绘制控件自身。 279 //如果 false，则不会引发 Paint 事件。 280 //此样式仅适用于从 Control 派生的类 281 SetStyle(ControlStyles.UserPaint, true); 282 283 //控件会在调整大小时进行重绘 284 SetStyle(ControlStyles.ResizeRedraw, true); 285 286 //如果为 true，则控件接受 alpha 组件数小于 255 个的 BackColor 来模拟透明度。 287 //仅当将 UserPaint 位设置为 true 且父控件从 Control 派生时，才会模拟透明度。 288 SetStyle(ControlStyles.SupportsTransparentBackColor, true); 289 this.BackColor = Color.Transparent; 290 291 m_LinearGradientRect = this.ClientRectangle; 292 } 293 #endregion 294 295 #region 02继承函数 -- 通过控件OnPaint方法把构造函数所箭头路径绘制出来（e.Graphics.FillPath(b, m_gp);） 296 297 /// <summary> 298 /// 控件Size改变时，触发OnResize方法 299 /// </summary> 300 /// <param name="e"></param> 301 protected override void OnResize(EventArgs e) 302 { 303 Clear(); 304 Init(); 305 Refresh(); 306 } 307 308 /// <summary> 309 /// 控件重绘时，触发OnPaint方法 310 /// </summary> 311 /// <param name="e"></param> 312 protected override void OnPaint(PaintEventArgs e) 313 { 314 //开始颜色 315 m_ColorS = NormalStartColor; 316 //结束颜色 317 m_ColorE = NormalEndColor; 318 319 //设置渐变区域Rectangle 320 Rectangle rect = this.ClientRectangle; 321 if (m_LinearGradientUsingClient) 322 { 323 rect = this.ClientRectangle; 324 } 325 else 326 { 327 rect = this.RectangleToClient(m_LinearGradientRect); 328 } 329 330 //使用线性渐变绘制区域 331 LinearGradientBrush b = null; 332 if (ColorLinearDirection == LinearGradientDirection.Horizontal) 333 { 334 b = new LinearGradientBrush(rect, m_ColorS, m_ColorE, 0, false); 335 } 336 else 337 { 338 b = new LinearGradientBrush(rect, m_ColorS, m_ColorE, 90, false); 339 } 340 341 // 设计模式 342 if (this.DesignMode != true) 343 { 344 //setClip方法的原理是通过只在屏幕上显示一部分内容，让图片恰好位于该部分的内容显示出来。 345 //把e.Graphics 的区域大小设置为绘画区域一致， 346 e.Graphics.SetClip(m_gp); 347 } 348 349 //SmoothingModeAntiAlias 指定消除锯齿的呈现。 350 //SmoothingModeDefault 指定默认模式。 351 //SmoothingModeHighQuality 指定高质量、低速度呈现。 352 //SmoothingModeHighSpeed 指定高速度、低质量呈现。 353 //SmoothingModeInvalid 指定一个无效模式。 354 //SmoothingModeNone 指定不消除锯齿。 355 //反走样 356 if (m_antiAlias) 357 { 358 e.Graphics.SmoothingMode = SmoothingMode.AntiAlias; 359 } 360 else 361 { 362 e.Graphics.SmoothingMode = SmoothingMode.None; 363 } 364 365 e.Graphics.FillPath(b, m_gp); //填充路径 366 b.Dispose(); 367 368 //划框 369 if (m_FrameEnabled) 370 { 371 ColorArrowFrame(e); 372 } 373 } 374 375 #endregion 376 377 #region 方法 -- 设置控件形状：1.坐标 2.绘制路径 378 379 private void Clear() 380 { 381 // 清除箭头坐标数组 382 m_pnts = null; 383 // 清空 PathPoints 和 PathTypes 数组并将 FillMode 设置为 Alternate。 384 m_gp.Reset(); 385 } 386 387 /// <summary> 388 /// 箭头框架 389 /// </summary> 390 /// <param name="e"></param> 391 private void ColorArrowFrame(PaintEventArgs e) 392 { 393 Pen p1 = null; 394 { 395 if (this.Width < this.Height) 396 { 397 for (int i = 0; i < m_pCount - 1; i++) 398 { 399 if (m_pnts[i].Y <= m_pnts[i + 1].Y) 400 { 401 p1 = new Pen(SystemColors.ControlLightLight, 1f); 402 } 403 else 404 { 405 p1 = new Pen(SystemColors.ControlDark, 1f); 406 } 407 e.Graphics.DrawLine(p1, m_pnts[i].X, m_pnts[i].Y, m_pnts[i + 1].X, m_pnts[i + 1].Y); 408 } 409 } 410 else 411 { 412 for (int i = 0; i < m_pCount - 1; i++) 413 { 414 if (m_pnts[i].Y > m_pnts[i + 1].Y) 415 { 416 p1 = new Pen(SystemColors.ControlLightLight, 1f); 417 } 418 else 419 { 420 p1 = new Pen(SystemColors.ControlDark, 1f); 421 } 422 e.Graphics.DrawLine(p1, m_pnts[i].X, m_pnts[i].Y, m_pnts[i + 1].X, m_pnts[i + 1].Y); 423 } 424 } 425 } 426 } 427 428 /// <summary> 429 /// 初期化 430 /// 1.定义箭头坐标 431 /// 2.根据箭头坐标设置绘制路径 432 /// </summary> 433 private void Init() 434 { 435 //MakeSquare(); 436 437 // 产生箭头坐标 438 BuildInitialArrow(); 439 440 // 绘制路径 441 GraphicsPathFromPoints(m_pnts, m_gp); 442 } 443 444 //private void MakeSquare() 445 //{ 446 // this.SuspendLayout(); 447 // if (this.Width < MINSIZE) 448 // { 449 // this.Size = new Size(MINSIZE, MINSIZE); 450 // } 451 // else 452 // { 453 // if (this.Size.Width < this.Size.Height) 454 // { 455 // this.Size = new Size(this.Size.Width, this.Size.Width); 456 // } 457 // else 458 // { 459 // this.Size = new Size(this.Size.Height, this.Size.Height); 460 // } 461 // } 462 // this.ResumeLayout(); 463 //} 464 465 /// <summary> 466 /// 创建箭头坐标组 467 /// </summary> 468 private void BuildInitialArrow() 469 { 470 float dx = this.Width - 2; 471 float dy = this.Height - 2; 472 473 if (m_FrameEnabled == false) 474 { 475 dx = this.Width; 476 dy = this.Height; 477 } 478 479 switch (m_ArrowType) 480 { 481 case ArrowStyleType.None: 482 m_pCount = 5; 483 m_pnts = new PointF[m_pCount]; 484 485 m_pnts[0] = new PointF(0, 0); 486 m_pnts[1] = new PointF(dx, 0); 487 m_pnts[2] = new PointF(dx, dy); 488 m_pnts[3] = new PointF(0, dy); 489 m_pnts[4] = new PointF(0, 0); 490 break; 491 case ArrowStyleType.Top: 492 m_pCount = 8; 493 m_pnts = new PointF[m_pCount]; 494 495 m_pnts[0] = new PointF((dx - m_ArrowBodyWidth) / 2f, dy); 496 m_pnts[1] = new PointF((dx - m_ArrowBodyWidth) / 2f, m_ArrowLength); 497 m_pnts[2] = new PointF(0, m_ArrowLength); 498 m_pnts[3] = new PointF(dx / 2f, 0); 499 m_pnts[4] = new PointF(dx, m_ArrowLength); 500 m_pnts[5] = new PointF(dx / 2f + m_ArrowBodyWidth / 2f, m_ArrowLength); 501 m_pnts[6] = new PointF(dx / 2f + m_ArrowBodyWidth / 2f, dy); 502 m_pnts[7] = new PointF((dx - m_ArrowBodyWidth) / 2f, dy); 503 break; 504 case ArrowStyleType.Left: 505 m_pCount = 8; 506 m_pnts = new PointF[m_pCount]; 507 m_pnts[0] = new PointF(dx, dy / 2f - m_ArrowBodyWidth / 2f); 508 m_pnts[1] = new PointF(m_ArrowLength, dy / 2f - m_ArrowBodyWidth / 2f); 509 m_pnts[2] = new PointF(m_ArrowLength, 0); 510 m_pnts[3] = new PointF(0, dy / 2f); 511 m_pnts[4] = new PointF(m_ArrowLength, dy); 512 m_pnts[5] = new PointF(m_ArrowLength, dy / 2f + m_ArrowBodyWidth / 2f); 513 m_pnts[6] = new PointF(dx, dy / 2f + m_ArrowBodyWidth / 2f); 514 m_pnts[7] = new PointF(dx, dy / 2f - m_ArrowBodyWidth / 2f); 515 break; 516 case ArrowStyleType.Right: 517 m_pCount = 8; 518 m_pnts = new PointF[m_pCount]; 519 m_pnts[0] = new PointF(0, dy / 2f - m_ArrowBodyWidth / 2f); 520 m_pnts[1] = new PointF(dx - m_ArrowLength, dy / 2f - m_ArrowBodyWidth / 2f); 521 m_pnts[2] = new PointF(dx - m_ArrowLength, 0); 522 m_pnts[3] = new PointF(dx, dy / 2f); 523 m_pnts[4] = new PointF(dx - m_ArrowLength, dy); 524 m_pnts[5] = new PointF(dx - m_ArrowLength, dy / 2f + m_ArrowBodyWidth / 2f); 525 m_pnts[6] = new PointF(0, dy / 2f + m_ArrowBodyWidth / 2f); 526 m_pnts[7] = new PointF(0, dy / 2f - m_ArrowBodyWidth / 2f); 527 break; 528 case ArrowStyleType.Bottom: 529 m_pCount = 8; 530 m_pnts = new PointF[m_pCount]; 531 m_pnts[0] = new PointF((dx - m_ArrowBodyWidth) / 2f, 0); 532 m_pnts[1] = new PointF((dx - m_ArrowBodyWidth) / 2f, dy - m_ArrowLength); 533 m_pnts[2] = new PointF(0, dy - m_ArrowLength); 534 m_pnts[3] = new PointF(dx / 2f, dy); 535 m_pnts[4] = new PointF(dx, dy - m_ArrowLength); 536 m_pnts[5] = new PointF(dx / 2f + m_ArrowBodyWidth / 2f, dy - m_ArrowLength); 537 m_pnts[6] = new PointF(dx / 2f + m_ArrowBodyWidth / 2f, 0); 538 m_pnts[7] = new PointF((dx - m_ArrowBodyWidth) / 2f, 0); 539 break; 540 case ArrowStyleType.LeftRight: 541 m_pCount = 11; 542 m_pnts = new PointF[m_pCount]; 543 m_pnts[0] = new PointF(0, dy / 2f); 544 m_pnts[1] = new PointF(m_ArrowLength, 0); 545 m_pnts[2] = new PointF(m_ArrowLength, dy / 2f - m_ArrowBodyWidth / 2f); 546 m_pnts[3] = new PointF(dx - m_ArrowLength, dy / 2f - m_ArrowBodyWidth / 2f); 547 m_pnts[4] = new PointF(dx - m_ArrowLength, 0); 548 m_pnts[5] = new PointF(dx, dy / 2f); 549 m_pnts[6] = new PointF(dx - m_ArrowLength, dy); 550 m_pnts[7] = new PointF(dx - m_ArrowLength, dy / 2f + m_ArrowBodyWidth / 2f); 551 m_pnts[8] = new PointF(m_ArrowLength, dy / 2f + m_ArrowBodyWidth / 2f); 552 m_pnts[9] = new PointF(m_ArrowLength, dy); 553 m_pnts[10] = new PointF(0, dy / 2f); 554 break; 555 case ArrowStyleType.TopBottom: 556 m_pCount = 11; 557 m_pnts = new PointF[m_pCount]; 558 m_pnts[0] = new PointF(dx / 2f, dy); 559 m_pnts[1] = new PointF(0, dy - m_ArrowLength); 560 m_pnts[2] = new PointF(dx / 2f - m_ArrowBodyWidth / 2f, dy - m_ArrowLength); 561 m_pnts[3] = new PointF(dx / 2f - m_ArrowBodyWidth / 2f, m_ArrowLength); 562 m_pnts[4] = new PointF(0, m_ArrowLength); 563 m_pnts[5] = new PointF(dx / 2f, 0); 564 m_pnts[6] = new PointF(dx, m_ArrowLength); 565 m_pnts[7] = new PointF(dx / 2f + m_ArrowBodyWidth / 2f, m_ArrowLength); 566 m_pnts[8] = new PointF(dx / 2f + m_ArrowBodyWidth / 2f, dy - m_ArrowLength); 567 m_pnts[9] = new PointF(dx, dy - m_ArrowLength); 568 m_pnts[10] = new PointF(dx / 2f, dy); 569 break; 570 case ArrowStyleType.UpBow: 571 m_pCount = 9; 572 m_pnts = new PointF[m_pCount]; 573 m_pnts[0] = new PointF(0, 0); 574 m_pnts[1] = new PointF(0, dy); 575 m_pnts[2] = new PointF(dx, dy); 576 m_pnts[3] = new PointF(dx, 0); 577 m_pnts[4] = new PointF(dx - m_BowWidth, 0); 578 m_pnts[5] = new PointF(dx - m_BowWidth, dy - m_BowHeight); 579 m_pnts[6] = new PointF(m_BowWidth, dy - m_BowHeight); 580 m_pnts[7] = new PointF(m_BowWidth, 0); 581 m_pnts[8] = new PointF(0, 0); 582 break; 583 case ArrowStyleType.DownBow: 584 m_pCount = 9; 585 m_pnts = new PointF[m_pCount]; 586 m_pnts[0] = new PointF(0, dy); 587 m_pnts[1] = new PointF(0, 0); 588 m_pnts[2] = new PointF(dx, 0); 589 m_pnts[3] = new PointF(dx, dy); 590 m_pnts[4] = new PointF(dx - m_BowWidth, dy); 591 m_pnts[5] = new PointF(dx - m_BowWidth, m_BowHeight); 592 m_pnts[6] = new PointF(m_BowWidth, m_BowHeight); 593 m_pnts[7] = new PointF(m_BowWidth, dy); 594 m_pnts[8] = new PointF(0, dy); 595 break; 596 case ArrowStyleType.LeftBow: 597 m_pCount = 9; 598 m_pnts = new PointF[m_pCount]; 599 m_pnts[0] = new PointF(0, 0); 600 m_pnts[1] = new PointF(dx, 0); 601 m_pnts[2] = new PointF(dx, dy); 602 m_pnts[3] = new PointF(0, dy); 603 m_pnts[4] = new PointF(0, dy - m_BowHeight); 604 m_pnts[5] = new PointF(dx - m_BowWidth, dy - m_BowHeight); 605 m_pnts[6] = new PointF(dx - m_BowWidth, m_BowHeight); 606 m_pnts[7] = new PointF(0, m_BowHeight); 607 m_pnts[8] = new PointF(0, 0); 608 break; 609 case ArrowStyleType.RightBow: 610 m_pCount = 9; 611 m_pnts = new PointF[m_pCount]; 612 m_pnts[0] = new PointF(0, 0); 613 m_pnts[1] = new PointF(dx, 0); 614 m_pnts[2] = new PointF(dx, m_BowHeight); 615 m_pnts[3] = new PointF(m_BowWidth, m_BowHeight); 616 m_pnts[4] = new PointF(m_BowWidth, dy - m_BowHeight); 617 m_pnts[5] = new PointF(dx, dy - m_BowHeight); 618 m_pnts[6] = new PointF(dx, dy); 619 m_pnts[7] = new PointF(0, dy); 620 m_pnts[8] = new PointF(0, 0); 621 break; 622 623 default: 624 break; 625 } 626 } 627 628 /// <summary> 629 /// 根据箭头坐标设置绘制路径 630 /// </summary> 631 /// <param name="pnts"></param> 632 /// <param name="gp"></param> 633 private void GraphicsPathFromPoints(PointF[] pnts, GraphicsPath gp) 634 { 635 for (int i = 0; i < pnts.Length - 1; i++) 636 { 637 gp.AddLine(pnts[i].X, pnts[i].Y, pnts[i + 1].X, pnts[i + 1].Y); 638 } 639 } 640 #endregion 641 642 #region 自定义控件默认值 643 644 /// <summary> 645 /// 自定义控件默认值 646 /// </summary> 647 private void InitializeComponent() 648 { 649 // 650 // ArrowLine 651 // 652 this.Name = "ArrowLine"; 653 this.Size = new System.Drawing.Size(48, 48); 654 } 655 656 #endregion 657 }
调用方式
在pictureBox1上添加控件，那么pictureBox1.AllowDrop = true;允许拖拽
1 ArrowControll objArrowControll = new ArrowControll(); 2 //objArrowControll.AntiAlias = false; 3 objArrowControll.ArrowBodyWidth = 8F; 4 objArrowControll.ArrowLength = 20F; 5 objArrowControll.ArrowStyle = ArrowStyleType.Left; 6 //objArrowControll.BowHeight = 4F; 7 //objArrowControll.BowWidth = 4F; 8 objArrowControll.ColorLinearDirection = LinearGradientDirection.Horizontal; 9 //objArrowControll.FrameEnabled = false; 10 //objArrowControll.LinearGradientRect = new System.Drawing.Rectangle(0, 0, 48, 48); 11 //objArrowControll.LinearGradientUsingClient = true; 12 objArrowControll.Location = new System.Drawing.Point(200, 100); 13 //objArrowControll.Name = "arrowLine1"; 14 objArrowControll.NormalEndColor = System.Drawing.Color.DarkOrange; 15 objArrowControll.NormalStartColor = System.Drawing.Color.Blue; 16 //objArrowControll.Size = new System.Drawing.Size(90, 22); 17 //objArrowControll.TabIndex = 3; 18 //objArrowControll.Text = "arrowLine1"; 19 20 //控件鼠标按下事件 21 objArrowControll.MouseDown += ObjArrowControll_MouseDown; 22 //控件鼠标移动事件 23 objArrowControll.MouseMove += ObjArrowControll_MouseMove; 24 //控件鼠标弹起事件 25 objArrowControll.MouseUp += ObjArrowControll_MouseUp; 26 27 pictureBox1.Controls.Add(objArrowControll);
控件事件
1 Point mouseDownPoint = new Point(); //记录拖拽过程鼠标位置 2 bool isMove = false; //判断鼠标在picturebox上移动时，是否处于拖拽过程(鼠标左键是否按下)
1 private void ObjArrowControll_MouseDown(object sender, MouseEventArgs e) 2 { 3 ArrowControll controll = (ArrowControll)sender; 4 //左键的话，标志位为true（表示拖拽开始） 5 if ((e.Button == System.Windows.Forms.MouseButtons.Left)) 6 { 7 mouseDownPoint.X = Cursor.Position.X; 8 mouseDownPoint.Y = Cursor.Position.Y; 9 isMove = true; 10 controll.Focus(); 11 } 12 } 13 private void ObjArrowControll_MouseMove(object sender, MouseEventArgs e) 14 { 15 ArrowControll controll = (ArrowControll)sender; 16 if (isMove) 17 { 18 int x, y; 19 int moveX, moveY; 20 moveX = Cursor.Position.X - mouseDownPoint.X; 21 moveY = Cursor.Position.Y - mouseDownPoint.Y; 22 x = controll.Location.X + moveX; 23 y = controll.Location.Y + moveY; 24 controll.Location = new Point(x, y); 25 mouseDownPoint.X = Cursor.Position.X; 26 mouseDownPoint.Y = Cursor.Position.Y; 27 } 28 } 29 private void ObjArrowControll_MouseUp(object sender, MouseEventArgs e) 30 { 31 if (e.Button == MouseButtons.Left) 32 { 33 isMove = false; 34 } 35 }