制作模板文件，这里需要用到bartender软件，模板做成什么样，MES打印出来就是什么样子，MES负责将真实的数据放进模板里面打印出来。

2.创建打印服务程序，用来监听客户端的打印请求，关键代码如下：

using ax_mes_print.Model;

namespace ax_mes_print.Service;

public class CartonPrintService : IPrintService
{
    private readonly HttpHelper _httpHelper;
    private readonly ILogger<CartonPrintService> _logger;
    private readonly BartenderLabelHelper _bartenderLabelHelper;
    private const string folderName = "Carton";

    public CartonPrintService(HttpHelper httpHelper, ILogger<CartonPrintService> logger, BartenderLabelHelper bartenderLabelHelper)
    {
        _httpHelper = httpHelper;
        _logger = logger;
        _bartenderLabelHelper = bartenderLabelHelper;
    }

    public async Task<PrintResponse> ExecutePrintAsync(string printParameter)
    {
        var requestParameter = DeserializePrintRequest(printParameter);

        if (requestParameter == null)
        {
            return PrintResponse.Error("打印参数有误！");
        }
 

        if (string.IsNullOrWhiteSpace(requestParameter.CartonSN))
        {
            return PrintResponse.Error("卡通箱号不能为空！");
        }

        var LabelTemplateInfoList = await QueryLabelTemplateInfoAsync(requestParameter.ProductCode);

        if (LabelTemplateInfoList.Count == 0)
        {
            return PrintResponse.Error("未找卡通模板文件,请先上传！");
        }

        var cartonDataData = await QueryCartonDataAsync(requestParameter.CartonSN);

        if (cartonDataData == null || cartonDataData.Item2.Length == 0)
        {
            return PrintResponse.Error("未找到卡通数据,打印失败！");
        }

        var directory = FileHelper.CreateOrDeleteFolder(folderName);


        foreach (var item in LabelTemplateInfoList)
        {
            await _httpHelper.DownloadFileAsync(item.AccessUrl, folderName, item.FileName);

            var printReuslt = _bartenderLabelHelper.BartenderPrint(SetPrintName(requestParameter.PrintName), Path.Combine(directory, item.FileName), cartonDataData.Item1, cartonDataData.Item2);
            if (printReuslt != string.Empty)
            {
                return PrintResponse.Error(printReuslt);
            }
        }

        return PrintResponse.Success("打印命令发送成功,请查看打印机！");
    }

    private CartonPrintWebSocketRequest? DeserializePrintRequest(string printParameter)
    {
        if (string.IsNullOrWhiteSpace(printParameter))
        {
            return null;
        }

        var request = JsonConvert.DeserializeObject<CartonPrintWebSocketRequest>(printParameter);

        if (request is null)
        {
            return null;
        }

        return request;

    }

    private async Task<CartonDataData> QueryCartonDataAsync(string cartonSN)
    {
        var queryCartonDataResponse = null;

        return queryCartonDataResponse.Data;
    }

    private async Task<List<LabelTemplateInfo>> QueryLabelTemplateInfoAsync(string productCode)
    {
        var queryLabelTemplateInfoResponse = null;

        return queryLabelTemplateInfoResponse.Data;
    }

    
}

3.启动 MES 打印服务，该服务程序会监听客户端的打印请求，然后将打印任务传递给打印机。

4.在 MES 里面启动连接打印机，根据打印内容不同可以选择不同的打印机，如果忘了选择打印机，则系统以默认打印机为准.

 如图所示，我们在配置页面根据不同的打印类型设置了不同的打印机，当页面显示已连接的时候，MES通过打印服务将需要打印的内容传递给打印机，完成打印。