使用 C# 在 ASP.NET Framework Web 应用程序中进行打印

我应该在哪里添加打印按钮？

在您的"Index.cshtml"(或主页视图)中，添加一个按钮，点击该按钮将触发一个操作。 此按钮将在您的控制器中调用 ActionResult 方法：

@{
    ViewBag.Title = "Home Page";
}

<main>
    <section class="row" aria-labelledby="aspnetTitle">
        <h1 id="title">ASP.NET</h1>
        <p>

            <a class="btn btn-primary btn-md" onclick="location.href='@Url.Action("PrintPdf", "Home")'">Print PDF</a>
        </p>
    </section>
</main>

@{
    ViewBag.Title = "Home Page";
}

<main>
    <section class="row" aria-labelledby="aspnetTitle">
        <h1 id="title">ASP.NET</h1>
        <p>

            <a class="btn btn-primary btn-md" onclick="location.href='@Url.Action("PrintPdf", "Home")'">Print PDF</a>
        </p>
    </section>
</main>

如何在控制器中配置 PrintAsync？

在您的 HomeController 中，实现 PrintAsync 方法。 这种方法可以异步执行打印操作，提高应用程序的响应速度。 在实施之前，请确保许可证密钥配置正确，以便在生产中使用。

using IronPrint;
using System.Threading.Tasks;
using System.Web.Mvc;

namespace WebApplication4.Controllers
{
    public class HomeController : Controller
    {
        public ActionResult Index()
        {
            return View();
        }

        public ActionResult About()
        {
            ViewBag.Message = "Your application description page.";
            return View();
        }

        public ActionResult Contact()
        {
            return View();
        }

        // Action method to handle the printing operation
        // This makes use of the PrintAsync method to avoid blocking the main thread
        public ActionResult PrintPdf()
        {
            // Wait for the asynchronous print operation to complete
            Printer.PrintAsync("Basic.pdf").Wait();

            // Return some view, for example, a confirmation page or the index page
            return View(); // Replace with an appropriate view
        }
    }
}

using IronPrint;
using System.Threading.Tasks;
using System.Web.Mvc;

namespace WebApplication4.Controllers
{
    public class HomeController : Controller
    {
        public ActionResult Index()
        {
            return View();
        }

        public ActionResult About()
        {
            ViewBag.Message = "Your application description page.";
            return View();
        }

        public ActionResult Contact()
        {
            return View();
        }

        // Action method to handle the printing operation
        // This makes use of the PrintAsync method to avoid blocking the main thread
        public ActionResult PrintPdf()
        {
            // Wait for the asynchronous print operation to complete
            Printer.PrintAsync("Basic.pdf").Wait();

            // Return some view, for example, a confirmation page or the index page
            return View(); // Replace with an appropriate view
        }
    }
}

对于高级场景，应实施适当的异步/等待模式并自定义打印操作。 下面是一个增强示例，演示了错误处理和自定义打印设置：

using IronPrint;
using System;
using System.Threading.Tasks;
using System.Web.Mvc;

namespace WebApplication4.Controllers
{
    public class HomeController : Controller
    {
        // Async action method with proper error handling
        public async Task<ActionResult> PrintPdfAdvanced()
        {
            try
            {
                // Create custom print settings
                var printSettings = new PrintSettings
                {
                    // Select specific printer
                    PrinterName = "Microsoft Print to PDF",
                    // Set paper size
                    PaperSize = PaperSize.A4,
                    // Configure orientation
                    PaperOrientation = PaperOrientation.Portrait,
                    // Set number of copies
                    NumberOfCopies = 1,
                    // Configure DPI for high-quality output
                    Dpi = 300
                };

                // Print asynchronously with custom settings
                await Printer.PrintAsync("Basic.pdf", printSettings);

                // Log successful print operation (optional)
                System.Diagnostics.Debug.WriteLine("Document printed successfully");

                // Return success view or redirect
                TempData["PrintMessage"] = "Document sent to printer successfully!";
                return RedirectToAction("Index");
            }
            catch (Exception ex)
            {
                // Handle printing errors gracefully
                System.Diagnostics.Debug.WriteLine($"Printing error: {ex.Message}");
                TempData["ErrorMessage"] = "Unable to print document. Please try again.";
                return RedirectToAction("Index");
            }
        }
    }
}

using IronPrint;
using System;
using System.Threading.Tasks;
using System.Web.Mvc;

namespace WebApplication4.Controllers
{
    public class HomeController : Controller
    {
        // Async action method with proper error handling
        public async Task<ActionResult> PrintPdfAdvanced()
        {
            try
            {
                // Create custom print settings
                var printSettings = new PrintSettings
                {
                    // Select specific printer
                    PrinterName = "Microsoft Print to PDF",
                    // Set paper size
                    PaperSize = PaperSize.A4,
                    // Configure orientation
                    PaperOrientation = PaperOrientation.Portrait,
                    // Set number of copies
                    NumberOfCopies = 1,
                    // Configure DPI for high-quality output
                    Dpi = 300
                };

                // Print asynchronously with custom settings
                await Printer.PrintAsync("Basic.pdf", printSettings);

                // Log successful print operation (optional)
                System.Diagnostics.Debug.WriteLine("Document printed successfully");

                // Return success view or redirect
                TempData["PrintMessage"] = "Document sent to printer successfully!";
                return RedirectToAction("Index");
            }
            catch (Exception ex)
            {
                // Handle printing errors gracefully
                System.Diagnostics.Debug.WriteLine($"Printing error: {ex.Message}");
                TempData["ErrorMessage"] = "Unable to print document. Please try again.";
                return RedirectToAction("Index");
            }
        }
    }
}

该增强实施展示了打印设置指南中的概念，包括指定打印机名称、配置纸张大小和适当处理错误。

在网络环境中选择打印机时，可利用 Get Printer Names 功能动态填充可用打印机列表：

// Get list of available printers
public ActionResult GetAvailablePrinters()
{
    var printers = Printer.GetPrinterNames();
    ViewBag.PrinterList = new SelectList(printers);
    return View();
}

// Get list of available printers
public ActionResult GetAvailablePrinters()
{
    var printers = Printer.GetPrinterNames();
    ViewBag.PrinterList = new SelectList(printers);
    return View();
}

对于需要用户交互的场景，可以考虑采用 Print with Dialog 方法，不过这种方法更适合桌面应用程序而非网络环境。