我有一个网页，其中有一个功能，当我们点击pdf时，它会随时取出打印机的值。这需要一些时间，因此在重复点击时，网页会崩溃。
有没有办法让我们可以中止当前运行的功能，或者可以在点击后以某种方式禁用按钮点击？
UI代码：
<asp:UpdatePanel ID="UpdatePanel2" runat="server">
<Triggers>
<asp:PostBackTrigger ControlID="imgExportPDF" />
</Triggers>
<ContentTemplate>
<table id="topHeading" width="100%" cellspacing="0" cellpadding="0" border="0" class="PageHeader">
<tr align="center" style="height: 25px" class="PageHeader2">
<td>
</td>
<td align="right" valign="bottom" style="width: 30%" visible="false">
<asp:ImageButton ID="imgExportPDF" runat="server" ImageUrl="~/Images/pdf-Export.jpg"
</td>
</tr>
</table>
</ContentTemplate>
</asp:UpdatePanel>
我的后端代码：
protected void imgExportPDF_Click(object sender, ImageClickEventArgs e)
{
saveDetails();
int counterAdd = 0;
DataSet dsDevNotReady = CDBIntract.GetDevNotReady(EnterpriseV, CDInfonew.Count);
if (dsDevNotReady != null)
{
if (dsDevNotReady.Tables[0].Rows.Count > 0)
{
for (int i = 0; i < dsDevNotReady.Tables[0].Rows.Count; i++)
{
sb.Append((deviceCounter + 1) + ". IP Address : " + dsDevNotReady.Tables[0].Rows[i]["IPAddress"].ToString() + " And Model Name : " + dsDevNotReady.Tables[0].Rows[i]["Model"].ToString() + " On Date : " + DateTime.Now.ToString() + " " + dsDevNotReady.Tables[0].Rows[i]["Info"].ToString());
sb.Append("\r\n");
deviceCounter++;
}
counterAdd++;
}
}
int countData = 0;
DataSet dsdev= CDBIntract.Blah(EnterpriseV, CDInfonew.Count);
if (dsDev != null)
{
if (dsDev.Tables[0].Rows.Count > 0)
{
countData = dsDev.Tables[0].Rows.Count + Convert.ToInt32(dsDev.Tables[1].Rows[0]["AditionalRows1"].ToString()) + Convert.ToInt32(dsDev.Tables[2].Rows[0]["AditionalRows2"].ToString());
PdfDocument myPdfDocument = new PdfDocument(PdfDocumentFormat.A4);
PdfTable myPdfTable = myPdfDocument.NewTable(new Font("Verdana", 8), countData + counterAdd, 2, 4);
myPdfTable.ImportDataTable(returnTable(dsDev, deviceCounter, sb.ToString()));
//Set PDF Table Style
myPdfTable.HeadersRow.SetFont(new Font("Arial", 8, FontStyle.Bold));
myPdfTable.HeadersRow.SetColors(System.Drawing.Color.Gray, System.Drawing.Color.Gray);
myPdfTable.SetColors(Color.Black, Color.White, Color.White);
myPdfTable.SetBorders(Color.Gray, 1, BorderType.CompleteGrid);
myPdfTable.SetColumnsWidth(new int[] { 30, 30 });
int[] arrayDevice = listDevice.ToArray();
for (int m = 0; m < arrayDevice.Length; m++)
{
try
{
foreach (PdfCell pc in myPdfTable.CellRange(arrayDevice[m], 0, arrayDevice[m], 0).Cells)
{
pc.ColSpan = 2;
pc.SetCellPadding(4);
pc.SetColors(Color.Red, Color.LightGray);
pc.SetFont(new Font("Arial", 10, FontStyle.Bold));
}
}
catch (Exception ex)
{ }
}
int[] array = list.ToArray();
for (int m = 0; m < array.Length; m++)
{
try
{
foreach (PdfCell pc in myPdfTable.CellRange(array[m], 0, array[m], 0).Cells)//(0//,0//,0//Number of rows,0//column)
{
pc.ColSpan = 2;
pc.SetCellPadding(4);
pc.SetColors(Color.Blue, Color.LightGray);
pc.SetFont(new Font("Arial", 10, FontStyle.Bold));
}
}
catch (Exception ex)
{ }
}
int[] array1 = list2.ToArray();
for (int n = 0; n < array1.Length; n++)
{
try
{
foreach (PdfCell pc in myPdfTable.CellRange(array1[n], 0, array1[n], 0).Cells)//(0//,0//,0//Number of rows,0//column)
{
pc.ColSpan = 2;
pc.SetCellPadding(4);
pc.SetColors(Color.Blue, Color.LightGray);
pc.SetFont(new Font("Arial", 8, FontStyle.Bold));
}
}
catch (Exception ex)
{ }
}
int[] array2 = list3.ToArray();
for (int k = 0; k < array2.Length; k++)
{
try
{
foreach (PdfCell pc in myPdfTable.CellRange(array2[k], 0, array2[k], 0).Cells)//(0//,0//,0//Number of rows,0//column)
{
pc.ColSpan = 2;
pc.SetCellPadding(4);
//pc.SetColors(Color.Blue, Color.LightGray);
if (k == 0)
pc.SetFont(new Font("Arial", 8, FontStyle.Bold));
}
}
catch (Exception ex)
{
}
}
myPdfTable.SetRowHeight(100);
// Now we set some alignment... for the whole table and then, for a column.
myPdfTable.SetContentAlignment(ContentAlignment.MiddleLeft);
string logo = HttpContext.Current.Server.MapPath(".") + "/images/Printeaze_Logo02.jpg";
PdfImage LogoImage = myPdfDocument.NewImage(logo);
string companylogo = HttpContext.Current.Server.MapPath(".") + "/images/CompanyLogo.jpg";
PdfImage CompanyLogo = myPdfDocument.NewImage(companylogo);
int i = 0;
PdfTablePage newPdfTablePage;
// Here we start the loop to generate the table...
while (!myPdfTable.AllTablePagesCreated)
{
// we create a new page to put the generation of the new TablePage:
i++;
PdfPage newPdfPage = myPdfDocument.NewPage();
if (i == 1)
{
newPdfTablePage =
myPdfTable.CreateTablePage(new PdfArea(myPdfDocument, 18, 120, 560, 680));
// newPdfTablePage =
// myPdfTable.CreateTablePage(new PdfArea(myPdfDocument, 18, 120, 560, 450));
newPdfPage.Add(LogoImage, 460, 30, 120);
newPdfPage.Add(CompanyLogo, 20, 20, 120);
// we also put a Label
PdfTextArea pta = new PdfTextArea(new Font("Verdana", 16, FontStyle.Bold), Color.Black
, new PdfArea(myPdfDocument, 20, 70, 350, 20), ContentAlignment.MiddleLeft, "Blah");
newPdfPage.Add(newPdfTablePage);
newPdfPage.Add(pta);
//PointF pointstart = new PointF(20, 140);
//PointF pointend = new PointF(578, 140);
}
else
{
newPdfTablePage = myPdfTable.CreateTablePage(new PdfArea(myPdfDocument, 18, 15, 560, 800));
// newPdfTablePage = myPdfTable.CreateTablePage(new PdfArea(myPdfDocument, 18, 15, 600, 650));
newPdfPage.Add(newPdfTablePage);
}
newPdfPage.SaveToDocument();
}
// Finally we save the docuement...
//myPdfDocument.SaveToFile("PDF.pdf");
MemoryStream stream = new MemoryStream();
myPdfDocument.SaveToStream(stream);
Response.ClearHeaders();
Response.ClearContent();
Response.ContentType = "application/pdf";
Response.AddHeader("content-disposition", "attachment; filename= Blah.pdf");
Response.BinaryWrite(stream.ToArray());
HttpContext.Current.ApplicationInstance.CompleteRequest();
}
}
}
答案 0 :(得分：0)
使用JavaScript在单击按钮时禁用该按钮。
如果这还不够，您需要跟踪（存储在静态列表或其他内容中）代码隐藏中的用户会话，并检查特定会话是否已启动但未完成PDF调用，只需退出副本如果第一个未完成则调用。
HttpContext.Current.Session
这将需要各种安全防护措施，这会增加复杂性，以防止用户在发生错误时完全锁定PDF生成。