Question

我有一个页面创建一个Itext pdf文档，然后下载文档。以下代码就是这样做的。但页面刷新。我想页面不必刷新。我认为这将提供更好的用户体验，使页面表单输入不会在页面刷新时消失。

是否有更好的方法来处理此任务，以便不必刷新页面？是否可以对现有代码进行一些修改以避免页面刷新？

labelReprint.js：

    $.ajax({
        url: "labelReprint.aspx/DoLabelPrint",
        data: "{'type':'" + lblType + "','scan':'" + scan + "','qty':'" + qty + "','split':'" + split + "'}",
        type: "POST",
        dataType: "json",
        contentType: "application/json; charset=utf-8",
        success: function (result) {
            console.log('Downloading .pdf');

            //pdf
            var downloadpdf = $('<a id="downloadpdf" download="' + fileName + '.pdf" href="data:application/pdf;base64,' + result.d + '" >');
            $('#download').append(downloadpdf);
            document.getElementById("downloadpdf").click();
            $("#downloadpdf").remove();

        },
        error: function (result) {
            console.log(result.responseJSON.Message + "\n\r\n\r" + result.responseJSON.StackTrace);
        }
    });

从上面的AJAX中引用的labelReprint.aspx / DoLabelPrint调用follow函数。这将处理Itext / pdf创建。

Public Shared Function mfgrLabel(ByVal barCode As String, ByVal user As String) As String
    Dim MS As System.IO.MemoryStream = New System.IO.MemoryStream()

    Dim subs = New subs

    Dim pSize As New iTextSharp.text.Rectangle(252, 36)
    Dim pdfDoc As New iTextSharp.text.Document(pSize, 0.0F, 0.0F, 0.0F, 0.0F)

    Dim writer As PdfWriter = PdfWriter.GetInstance(pdfDoc, MS)

    pdfDoc.Open()

    Dim cb As PdfContentByte = writer.DirectContent

    Dim tblLbl As iTextSharp.text.pdf.PdfPTable = New iTextSharp.text.pdf.PdfPTable(2)

    Dim bf As BaseFont = BaseFont.CreateFont(BaseFont.HELVETICA_BOLD, BaseFont.WINANSI, False)
    Dim tRsmall As iTextSharp.text.Font = iTextSharp.text.FontFactory.GetFont("Arial", 5, iTextSharp.text.Font.NORMAL)
    Dim tR As iTextSharp.text.Font = iTextSharp.text.FontFactory.GetFont("Arial", 6, iTextSharp.text.Font.NORMAL)
    Dim tRMed As iTextSharp.text.Font = iTextSharp.text.FontFactory.GetFont("Arial", 7, iTextSharp.text.Font.NORMAL)
    Dim tRMedLrg As iTextSharp.text.Font = iTextSharp.text.FontFactory.GetFont("Arial", 8, iTextSharp.text.Font.NORMAL)
    Dim tRLrg As iTextSharp.text.Font = iTextSharp.text.FontFactory.GetFont("Arial", 10, iTextSharp.text.Font.NORMAL)
    Dim tXRLrg As iTextSharp.text.Font = iTextSharp.text.FontFactory.GetFont("Arial", 12, iTextSharp.text.Font.NORMAL)

    Dim cBlankNB As iTextSharp.text.pdf.PdfPCell = New iTextSharp.text.pdf.PdfPCell

    cBlankNB.Border = 0

    tblLbl.HorizontalAlignment = 0

    '***************  Labels ***************************
    Dim cellTimestamp As iTextSharp.text.pdf.PdfPCell = New iTextSharp.text.pdf.PdfPCell(New iTextSharp.text.Phrase(barCode, tR)) '"Inovar P/N:"
    Dim cPartNo As iTextSharp.text.pdf.PdfPCell = New iTextSharp.text.pdf.PdfPCell(New iTextSharp.text.Phrase(barCode.Split("|")(0) & " " & barCode.Split("|")(1), tRMedLrg))

    Dim uInfo As String = user.ToUpper & " " & Now.ToString("dd-MMM-yyyy").ToUpper

    Dim pInfo As String = barCode.Split("|")(0) & " " & barCode.Split("|")(1)

    cellTimestamp.Border = 0

    cPartNo.Border = 0
    '**************************************************

    '************  Bar Codes **************************

    Dim safeFileName As String = subs.fixFileNameBeforeSave(barCode.Split("|")(1))
    Dim inoDm As Barcodes.DataMatrix.DataMatrixWebControl = New Barcodes.DataMatrix.DataMatrixWebControl
    inoDm.DataToEncode = barCode.Split("|")(1)
    If File.Exists(HttpContext.Current.Server.MapPath(safeFileName & ".jpg")) Then
        File.Delete(HttpContext.Current.Server.MapPath(safeFileName & ".jpg"))
    End If

    inoDm.SaveToImageFile(25, 25, HttpContext.Current.Server.MapPath(safeFileName & ".jpg"), 300, Barcodes.DataMatrix.Dimensions.dmMM)

    Dim inoDmImg As iTextSharp.text.Image
    inoDmImg = iTextSharp.text.Image.GetInstance(HttpContext.Current.Server.MapPath(safeFileName & ".jpg"))

    inoDmImg.ScaleAbsolute(25, 25)

    Dim inoPBC As iTextSharp.text.pdf.PdfPCell
    inoPBC = New iTextSharp.text.pdf.PdfPCell(iTextSharp.text.Image.GetInstance(inoDmImg))

    inoPBC.VerticalAlignment = 6
    inoPBC.HorizontalAlignment = 0
    inoPBC.Border = 0
    inoPBC.PaddingLeft = 10.0F
    inoPBC.PaddingTop = 15.0F
    '************  End Bar Codes **************************


    inoPBC.PaddingTop = 5.0F
    cPartNo.NoWrap = True
    inoPBC.Colspan = 2

    tblLbl.AddCell(inoPBC)

    pdfDoc.Add(tblLbl)

    cb.SetFontAndSize(bf, 8)
    cb.BeginText()
    cb.ShowTextAligned(PdfContentByte.ALIGN_LEFT, pInfo, 40, 20, 0) '180
    cb.EndText()

    cb.SetFontAndSize(bf, 4)
    cb.BeginText()
    cb.ShowTextAligned(PdfContentByte.ALIGN_LEFT, uInfo, 40, 4, 0) '180
    cb.EndText()

    pdfDoc.Close()

    'Clean up
    If File.Exists(HttpContext.Current.Server.MapPath(safeFileName & ".jpg")) Then
        File.Delete(HttpContext.Current.Server.MapPath(safeFileName & ".jpg"))
    End If

    Return System.Convert.ToBase64String(MS.ToArray())

任何想法或见解都将非常受欢迎。

Answer 1

在Ajax的完成中，输入以下代码：

var binaryString = window.atob(result);
var binaryLen = binaryString.length;
var bytes = new Uint8Array(binaryLen);
for (var idx = 0; idx < binaryLen; idx++) {
            var ascii = binaryString.charCodeAt(idx);
            bytes[idx] = ascii;
}
var blob = new Blob([bytes]);
var link = document.createElement('a');
link.href = window.URL.createObjectURL(blob);
var fileName = "filename.pdf";
link.download = fileName;
link.click();

使用JS / AJAX下载IText .pdf

1 个答案: