分享一个自定义打印套打方案

最近项目中需要实现单据套打的功能,实现后,留此日记以备忘,同时为有类似需求的同学提供一种解决方案.

原始需求:

1. 打印模板支持灵活自定义,支持可视化设置(含设置打印项是否打印,及位置,大小,字体等…).

2. 支持自定义打印项.

3. 常规的打印项设置(如自动打印小计/合计,表头表尾等…)

4. 在设置模板的时候,支持实时预览.

首先,先上个图, 给大家看一下打印套打模板的大致效果图,各位同学看着顺眼再往下看.

接下来,我们简单的来讨论一下如何实现这个需求,简单分析一下,在这个功能中,可能需要存在以下角色对象.

1. 打印项: 姑且暂称为 PrintItem ,我们不难发现至少应该具备以下属性: 标签名称, 数据源, 宽度, 高度, 字体, 颜色, 对齐方式, 打印坐标(表明细区域可能为打印位置索引)…

2. 打印模板数据: 姑且暂称为 BillPrintData , 为了简单起见,我们可以将这个打印模板数据拆分为 表头, 表体, 表尾,因为表头和表尾在控制上行为基本上是一致的,由此我们很自然的衍生出来了 表头表尾 以及 中间的”表体 ”这两个对象.

3. 表头表尾: 姑且暂称为 BillHeaderOrBottom ,不难看出,其理所应当的应该包含一个打印项集合,一个为这些打印项赋值的数据源. 以及这个区域的大小和其实坐标位置.

4. 表体即中间表格部分,姑且暂称为 BillGridBody, 具有和 BillHeaderOrBottom 一样的内容,同时还应该有设置那些行需要小计/合计.

5. 打印控制器,姑且暂称为  BillPrinter , 主要功能为加载打印格式,同时根据参数配置,控制输出到打印机.

有了上面的简单分析,我们来简单画一下这个需求的类结构图.

有了上面这些分析,下面我们一起来看下如何来实现这个功能.我们先来实现一个可运行状态随意拖动的容器控件.

为了简单起见,这里我们不妨就暂称我们将要扩展的Panel容器名称为 MoveControlPanel,该容器至少需要实现以下功能

1. 识别当前鼠标位置,是否处于某个内部组件的边框位置,以让鼠标显示出对应的图标(拉伸,移动…)

2.移动鼠标以改变内部某个组件的大小及坐标,

3.保存容器内每个组件的当前坐标及大小.

为了便于描述当前光标状态,我们不妨定义一个枚举.姑且称其为 EMousePointPosition, 其至少应该具有如下定义.

       /// <summary>
        /// 光标状态
        /// </summary>
        private enum EMousePointPosition
        {
            /// <summary>
            /// 无
            /// </summary>
            None = 0,

            /// <summary>
            /// 处于拉伸右边框位置
            /// </summary>
            MouseSizeRight = 1,

            /// <summary>
            /// 处于拉伸左边框位置
            /// </summary>
            MouseSizeLeft = 2,

            /// <summary>
            /// 处于拉伸下边框位置
            /// </summary>
            MouseSizeBottom = 3,

            /// <summary>
            /// 处于拉伸上边框位置
            /// </summary>
            MouseSizeTop = 4,

            /// <summary>
            /// 处于拉伸左上角位置
            /// </summary>
            MouseSizeTopLeft = 5,

            /// <summary>
            /// 处于拉伸右上角位置
            /// </summary>
            MouseSizeTopRight = 6,

            /// <summary>
            /// 处于拉伸左小角位置
            /// </summary>
            MouseSizeBottomLeft = 7,

            /// <summary>
            /// 处于拉伸右下角位置
            /// </summary>
            MouseSizeBottomRight = 8,

            /// <summary>
            /// 鼠标拖动状态
            /// </summary>
            MouseDrag = 9
        }

接下来,我们需要通过处理容器内控件的 鼠标按下/鼠标移动/鼠标离开 三个事件,来实现对容器内各个控件的大小/位置的改变.

/// <summary>
/// 初始化鼠标事件
/// </summary>
public void InitMouseEvent()
{
  for (int i = 0; i < this.Controls.Count; i++)
    {
      this.Controls[i].MouseDown += new System.Windows.Forms.MouseEventHandler(ctrl_MouseDown);
      this.Controls[i].MouseLeave += new System.EventHandler(ctrl_MouseLeave);
      this.Controls[i].MouseMove += new System.Windows.Forms.MouseEventHandler(ctrl_MouseMove);
     }
}

接下来我们去尝试实现以下鼠标移动事件,

1) 如果当前没有按下鼠标按键,则去尝试获取当前鼠标的状态,并设置当前光标样式

2) 当按下了鼠标左键,此时需要根据光标状态来改变当前控件的坐标/大小.

private const int Band = 5;                                     //边框大小
 private const int MinWidth = 10;                            //最小宽度
 private const int MinHeight = 10;                           //最小高度
 private EMousePointPosition _currentMousePointPosition;     //当前鼠标状态
 private Point p, p1;                                        //临时变量,缓存改变前后鼠标坐标

        /// <summary>
        /// 获取鼠标坐标状态
        /// </summary>
        /// <param name="size">当前控件大小</param>
        /// <param name="e">当前鼠标坐标位置</param>
        /// <returns></returns>
        private EMousePointPosition GetMousePointPosition(Size size, Point e)
        {
            if ((e.X >= -1 * Band) | (e.X <= size.Width) | (e.Y >= -1 * Band) | (e.Y <= size.Height))
            {
                if (e.X < Band)
                {
                    if (e.Y < Band)
                    {
                        return EMousePointPosition.MouseSizeTopLeft;
                    }
                    else
                    {
                        if (e.Y > -1 * Band + size.Height)
                        {
                            return EMousePointPosition.MouseSizeBottomLeft;
                        }
                        else
                        {
                            return EMousePointPosition.MouseSizeLeft;
                        }
                    }
                }
                else
                {
                    if (e.X > -1 * Band + size.Width)
                    {
                        if (e.Y < Band)
                        {
                            return EMousePointPosition.MouseSizeTopRight;
                        }
                        else
                        {
                            if (e.Y > -1 * Band + size.Height)
                            {
                                return EMousePointPosition.MouseSizeBottomRight;
                            }
                            else
                            {
                                return EMousePointPosition.MouseSizeRight;
                            }
                        }
                    }
                    else
                    {
                        if (e.Y < Band)
                        {
                            return EMousePointPosition.MouseSizeTop;
                        }
                        else
                        {
                            if (e.Y > -1 * Band + size.Height)
                            {
                                return EMousePointPosition.MouseSizeBottom;
                            }
                            else
                            {
                                return EMousePointPosition.MouseDrag;
                            }
                        }
                    }
                }
            }
            else
            {
                return EMousePointPosition.None;
            }
        }

/// <summary>
        /// 设置光标状态
        /// </summary>
        /// <param name="e">当前引发的鼠标事件参数</param>
        /// <param name="tempCtrl">当前控件大小</param>
        private void SetCursorStyle(MouseEventArgs e, Control tempCtrl)
        {
            _currentMousePointPosition = GetMousePointPosition(tempCtrl.Size, e.Location);   //判断光标的位置状态   

            //根据光标位置状态设置当前鼠标状态
            switch (_currentMousePointPosition)
            {
                case EMousePointPosition.None:
                    this.Cursor = Cursors.Arrow;
                    break;
                case EMousePointPosition.MouseDrag:                 //移动效果
                    this.Cursor = Cursors.SizeAll;
                    break;
                case EMousePointPosition.MouseSizeBottom:           //上下边框              
                case EMousePointPosition.MouseSizeTop:
                    this.Cursor = Cursors.SizeNS;
                    break;
                case EMousePointPosition.MouseSizeLeft:             //左右边框
                case EMousePointPosition.MouseSizeRight:
                    this.Cursor = Cursors.SizeWE;
                    break;
                case EMousePointPosition.MouseSizeBottomLeft:       //左上/右下
                case EMousePointPosition.MouseSizeTopRight:
                    this.Cursor = Cursors.SizeNESW;
                    break;
                case EMousePointPosition.MouseSizeBottomRight:      //右下左上
                case EMousePointPosition.MouseSizeTopLeft:
                    this.Cursor = Cursors.SizeNWSE;
                    break;
                default:
                    break;
            }
        }

/// <summary>
        /// 处理鼠标移动事件
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void ctrl_MouseMove(object sender, MouseEventArgs e)
        {
            Control tempCtrl = sender as Control;

            if (e.Button == MouseButtons.Left)
            {
                switch (_currentMousePointPosition)
                {
                    case EMousePointPosition.MouseDrag:
                        tempCtrl.Left = tempCtrl.Left + e.X - p.X;
                        tempCtrl.Top = tempCtrl.Top + e.Y - p.Y;
                        break;
                    case EMousePointPosition.MouseSizeBottom:
                        tempCtrl.Height = tempCtrl.Height + e.Y - p1.Y;
                        p1.X = e.X;
                        p1.Y = e.Y; //记录光标拖动的当前点   
                        break;
                    case EMousePointPosition.MouseSizeBottomRight:
                        tempCtrl.Width = tempCtrl.Width + e.X - p1.X;
                        tempCtrl.Height = tempCtrl.Height + e.Y - p1.Y;
                        p1.X = e.X;
                        p1.Y = e.Y; //记录光标拖动的当前点   
                        break;
                    case EMousePointPosition.MouseSizeRight:
                        tempCtrl.Width = tempCtrl.Width + e.X - p1.X;
                        //       lCtrl.Height = lCtrl.Height + e.Y - p1.Y;   
                        p1.X = e.X;
                        p1.Y = e.Y; //'记录光标拖动的当前点   
                        break;
                    case EMousePointPosition.MouseSizeTop:
                        tempCtrl.Top = tempCtrl.Top + (e.Y - p.Y);
                        tempCtrl.Height = tempCtrl.Height - (e.Y - p.Y);
                        break;
                    case EMousePointPosition.MouseSizeLeft:
                        tempCtrl.Left = tempCtrl.Left + e.X - p.X;
                        tempCtrl.Width = tempCtrl.Width - (e.X - p.X);
                        break;
                    case EMousePointPosition.MouseSizeBottomLeft:
                        tempCtrl.Left = tempCtrl.Left + e.X - p.X;
                        tempCtrl.Width = tempCtrl.Width - (e.X - p.X);
                        tempCtrl.Height = tempCtrl.Height + e.Y - p1.Y;
                        p1.X = e.X;
                        p1.Y = e.Y; //记录光标拖动的当前点   
                        break;
                    case EMousePointPosition.MouseSizeTopRight:
                        tempCtrl.Top = tempCtrl.Top + (e.Y - p.Y);
                        tempCtrl.Width = tempCtrl.Width + (e.X - p1.X);
                        tempCtrl.Height = tempCtrl.Height - (e.Y - p.Y);
                        p1.X = e.X;
                        p1.Y = e.Y; //记录光标拖动的当前点   
                        break;
                    case EMousePointPosition.MouseSizeTopLeft:
                        tempCtrl.Left = tempCtrl.Left + e.X - p.X;
                        tempCtrl.Top = tempCtrl.Top + (e.Y - p.Y);
                        tempCtrl.Width = tempCtrl.Width - (e.X - p.X);
                        tempCtrl.Height = tempCtrl.Height - (e.Y - p.Y);
                        break;
                    default:
                        break;
                }
                if (tempCtrl.Width < MinWidth) tempCtrl.Width = MinWidth;
                if (tempCtrl.Height < MinHeight) tempCtrl.Height = MinHeight;

            }
            else
            {
                SetCursorStyle(e, tempCtrl);
            }
        }

接下来,我们在处理一下鼠标按下及鼠标离开事件,

1) 鼠标按下,记录当前坐标

2) 鼠标离开,还原光标状态

/// <summary>
        /// 处理鼠标按下事件
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void ctrl_MouseDown(object sender, System.Windows.Forms.MouseEventArgs e)
        {
            if (e.Button == System.Windows.Forms.MouseButtons.Left)
            {
                p.X = e.X;
                p.Y = e.Y;
                p1.X = e.X;
                p1.Y = e.Y;
            }
        }
        /// <summary>
        /// 处理鼠标离开
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void ctrl_MouseLeave(object sender, EventArgs e)
        {
            _currentMousePointPosition = EMousePointPosition.None;
            this.Cursor = Cursors.Arrow;
        }

ok, 截止到这里,这个控件基本上就已完成了,已实现在界面中实时拖拽,改变大小功能.

此功能简略的讲解到这里,我想若有类似需求的朋友已经能知道后面的路怎么走了.剩下无非就是在一个设计器界面中引入这个控件,然后根据用户拖动的位置将坐标记录下来,在打印的时候,将数据源这个格式一起绑定后交给打印控制处理器负责打印即可.