C# Windows应用程序中如何在单页打印多张库存计数卡片

核心思路是在PrintPageEventHandler中维护当前打印的物品索引，通过计算行列布局在单页内绘制多张卡片，每次触发事件时完成一页内容的绘制，直到所有数据打印完毕。以下是完整的示例方案：

1. 数据模型定义 #

先对应数据库字段定义库存物品模型类：

public class InventoryItem
{
    public string ItemCode { get; set; }
    public string Location { get; set; }
    public int Quantity { get; set; }
    // 可按需添加其他打印字段
}

2. 窗体与打印逻辑实现 #

以WinForms为例，包含PrintPreviewControl的完整窗体代码：

using System;
using System.Collections.Generic;
using System.Drawing;
using System.Windows.Forms;

public partial class InventoryPrintForm : Form
{
    private PrintDocument _printDocument;
    private List<InventoryItem> _inventoryItems;
    private int _currentItemIndex = 0; // 跟踪当前打印的物品位置

    // 打印配置参数，可根据需求调整
    private readonly int _cardsPerPage = 10;
    private readonly int _columns = 2;
    private readonly int _rows = 5;
    private readonly int _cardWidth = 300; // 单位：百分之一英寸
    private readonly int _cardHeight = 150;
    private readonly int _marginLeft = 50;
    private readonly int _marginTop = 50;
    private readonly int _cardSpacing = 20;

    public InventoryPrintForm()
    {
        InitializeComponent();
        InitPrintComponents();
        LoadSampleData(); // 替换为数据库查询逻辑
    }

    private void InitPrintComponents()
    {
        _printDocument = new PrintDocument();
        _printDocument.PrintPage += PrintDocument_PrintPage;

        // 配置预览控件
        printPreviewControl1.Document = _printDocument;
        printPreviewControl1.Zoom = 0.5;
    }

    private void LoadSampleData()
    {
        _inventoryItems = new List<InventoryItem>();
        // 模拟95条数据，对应你的需求场景
        for (int i = 1; i <= 95; i++)
        {
            _inventoryItems.Add(new InventoryItem
            {
                ItemCode = $"ITEM-{i:D3}",
                Location = $"LOC-{i % 10 + 1}",
                Quantity = new Random().Next(1, 100)
            });
        }
    }

    private void PrintDocument_PrintPage(object sender, PrintPageEventArgs e)
    {
        int printedCount = 0;
        Graphics g = e.Graphics;

        // 逐行逐列绘制卡片
        for (int row = 0; row < _rows; row++)
        {
            for (int col = 0; col < _columns; col++)
            {
                if (_currentItemIndex >= _inventoryItems.Count) break;

                // 计算当前卡片的坐标
                int x = _marginLeft + col * (_cardWidth + _cardSpacing);
                int y = _marginTop + row * (_cardHeight + _cardSpacing);

                // 绘制卡片边框
                g.DrawRectangle(Pens.Black, x, y, _cardWidth, _cardHeight);

                // 填充卡片内容
                InventoryItem item = _inventoryItems[_currentItemIndex];
                float textY = y + 20;

                g.DrawString($"Item: {item.ItemCode}", new Font("Arial", 12, FontStyle.Bold), Brushes.Black, x + 15, textY);
                textY += 25;
                g.DrawString($"Location: {item.Location}", new Font("Arial", 10), Brushes.Black, x + 15, textY);
                textY += 25;
                g.DrawString($"Quantity: {item.Quantity}", new Font("Arial", 10), Brushes.Black, x + 15, textY);

                _currentItemIndex++;
                printedCount++;

                if (printedCount >= _cardsPerPage) break;
            }
            if (printedCount >= _cardsPerPage) break;
        }

        // 判断是否需要继续打印下一页
        e.HasMorePages = _currentItemIndex < _inventoryItems.Count;
        // 打印完成后重置索引，方便下次打印
        if (!e.HasMorePages) _currentItemIndex = 0;
    }

    // 预览按钮点击事件（需在窗体添加Button控件）
    private void btnPreview_Click(object sender, EventArgs e)
    {
        _currentItemIndex = 0;
        printPreviewControl1.Refresh();
    }
}

关键细节说明 #

• 状态维护：用类级别的_currentItemIndex跨PrintPage事件跟踪打印进度，确保多页打印时不会重复或遗漏数据。
• 布局计算：通过行列数、卡片尺寸和间距计算坐标，保证卡片在页面上均匀分布，可根据实际纸张大小调整参数。
• 单位说明：.NET打印类默认使用百分之一英寸作为单位，数值300对应实际3英寸宽度。
• 预览测试：PrintPreviewControl直接在窗体中展示打印效果，避免纸张浪费。

你可以根据实际需求调整卡片尺寸、行列布局、文本样式等参数，替换LoadSampleData方法为数据库查询逻辑即可对接真实数据。

内容的提问来源于stack exchange，提问作者DeepH2O