我从数据库中的json字符串导出pdf。 我的导出按钮位于gridview控件中 - 图像按钮。我正在使用Handler（ashx）文件进行导出。
问题是，导出页面上的按钮（一个按钮和一个命令字段）后没有回发。我的处理程序代码和aspx代码在
之下处理程序
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI.WebControls;
using iTextSharp.text;
using iTextSharp.text.pdf;
using iTextSharp.text.html;
using iTextSharp.text.html.simpleparser;
using System.IO;
using System.Web.UI;
using System.Data;
using GE.MSA.DataQuality.DataAccess;
using GE.MSA.DataQuality.DataAccess.Authentication;
using GE.MSA.DataQuality.DataAccess.EntityModel;
using Newtonsoft.Json;
namespace GE.MSA.DataQuality.Web
{
/// <summary>
/// Summary description for CreatePDF
/// </summary>
public class CreatePDF : IHttpHandler
{
public void ProcessRequest(HttpContext context)
{
//context.Response.ContentType = "text/plain";
//context.Response.Write("Hello World");
int _id = Convert.ToInt32(context.Request.QueryString["Id"]);
string _report = context.Request.QueryString["Report"];
string _lockedfrom = context.Request.QueryString["LockedFrom"];
string _lockedto = context.Request.QueryString["LockedTo"];
string _docheader = (_report == "CostServiceReport" ? "Cost & Service Report - " : "Service Report - ") + "Locked from : " + _lockedfrom + " to " + _lockedto;
string _doctitle = _report + "-" + _lockedfrom + "-" + _lockedto + ".pdf";
DataTable _PDFReport = new DataTable();
if (_report == "CostServiceReport")
{
using (var db = new dbReferenceTablesEntities())
{
string csr = (from i in db.CS_Billing_LockPeriod
where i.ID == _id
select i.CostServiceReport).FirstOrDefault().ToString();
_PDFReport = (DataTable)JsonConvert.DeserializeObject(csr, _PDFReport.GetType());
}
}
else
{
if (_report == "ServiceReport")
{
using (var db = new dbReferenceTablesEntities())
{
string sr = (from i in db.CS_Billing_LockPeriod
where i.ID == _id
select i.ServiceReport).FirstOrDefault().ToString();
_PDFReport = (DataTable)JsonConvert.DeserializeObject(sr, _PDFReport.GetType());
}
}
}
Document pdfDoc = new Document(PageSize.A3, 20, 20, 20, 20);
pdfDoc.SetPageSize(iTextSharp.text.PageSize.A3.Rotate());
try
{
PdfWriter.GetInstance(pdfDoc, System.Web.HttpContext.Current.Response.OutputStream);
pdfDoc.Open();
Chunk c = new Chunk("" + _docheader + "", FontFactory.GetFont("Verdana", 15));
Paragraph p = new Paragraph();
p.Alignment = Element.ALIGN_CENTER;
p.Add(c);
pdfDoc.Add(p);
string clientLogo = context.Server.MapPath(".") + "/images/abc.png";
string imageFilePath = context.Server.MapPath(".") + "/images/abc.png";
iTextSharp.text.Image jpg = iTextSharp.text.Image.GetInstance(imageFilePath);
//Resize image depend upon your need
jpg.ScaleToFit(60f, 40f);
//Give space before image
jpg.SpacingBefore = 0f;
//Give some space after the image
jpg.SpacingAfter = 1f;
jpg.Alignment = Element.HEADER;
pdfDoc.Add(jpg);
Font font8 = FontFactory.GetFont("ARIAL", 7);
DataTable dt = _PDFReport;
if (dt != null & dt.Rows.Count > 0)
{
//Craete instance of the pdf table and set the number of column in that table
PdfPTable PdfTable = new PdfPTable(dt.Columns.Count);
PdfTable.HeaderRows = 1;
PdfPCell PdfPCell = null;
for (int i = 0; i < dt.Columns.Count; i++)
{
PdfPCell = new PdfPCell(new Phrase(new Chunk(dt.Columns[i].ColumnName.ToString(), FontFactory.GetFont("Verdana", 12))));
PdfPCell.HorizontalAlignment = Element.ALIGN_CENTER;
PdfPCell.VerticalAlignment = Element.ALIGN_MIDDLE;
PdfPCell.BackgroundColor = new Color(109, 159, 213);
PdfTable.AddCell(PdfPCell);
}
for (int rows = 0; rows < dt.Rows.Count; rows++)
{
for (int column = 0; column < dt.Columns.Count; column++)
{
PdfPCell = new PdfPCell(new Phrase(new Chunk(dt.Rows[rows][column].ToString(), font8)));
PdfTable.AddCell(PdfPCell);
}
}
//PdfTable.SpacingBefore = 15f; // Give some space after the text or it may overlap the table
pdfDoc.Add(PdfTable); // add pdf table to the document
}
pdfDoc.Close();
context.Response.ContentType = "application/pdf";
context.Response.AddHeader("content-disposition", "attachment; filename= " + _doctitle);
System.Web.HttpContext.Current.Response.Write(pdfDoc);
context.Response.Flush();
HttpContext.Current.ApplicationInstance.CompleteRequest();
}
catch (DocumentException de)
{
System.Web.HttpContext.Current.Response.Write(de.Message);
}
catch (IOException ioEx)
{
System.Web.HttpContext.Current.Response.Write(ioEx.Message);
}
catch (Exception ex)
{
System.Web.HttpContext.Current.Response.Write(ex.Message);
}
}
public bool IsReusable
{
get
{
return false;
}
}
}
}
ASPX页面
<%@ Page Title="" Language="C#" MasterPageFile="~/Site1.Master" AutoEventWireup="true" CodeBehind="LockForcing.aspx.cs" Inherits="GE.MSA.DataQuality.Web.LockForcing" %>
<asp:Content ID="Content1" ContentPlaceHolderID="HeadContent" runat="server">
</asp:Content>
<asp:Content ID="Content2" ContentPlaceHolderID="MainContent" runat="server">
<asp:ScriptManager ID="scriptManager1" runat="server"></asp:ScriptManager>
<asp:UpdatePanel ID="up1" runat="server">
<ContentTemplate>
<h2>Lock Force Calculation</h2>
<div>
<fieldset>
<legend>Set Lock Period</legend>
<table>
<tr>
<td>
<label>Start Month</label></td>
<td>
<asp:DropDownList ID="ddlStartMonth" runat="server" Width="100%">
<asp:ListItem>01</asp:ListItem>
<asp:ListItem>02</asp:ListItem>
<asp:ListItem>03</asp:ListItem>
<asp:ListItem>04</asp:ListItem>
<asp:ListItem>05</asp:ListItem>
<asp:ListItem>06</asp:ListItem>
<asp:ListItem>07</asp:ListItem>
<asp:ListItem>08</asp:ListItem>
<asp:ListItem>09</asp:ListItem>
<asp:ListItem>10</asp:ListItem>
<asp:ListItem>11</asp:ListItem>
<asp:ListItem>12</asp:ListItem>
</asp:DropDownList></li></td>
<td></td>
<td>
<label>Start Year</label></td>
<td>
<asp:DropDownList ID="ddlStartYear" runat="server" Width="100%">
</asp:DropDownList></td>
</tr>
<tr>
<td>
<label>End Month</label></td>
<td>
<asp:DropDownList ID="ddlEndMonth" runat="server" Width="100%">
<asp:ListItem>01</asp:ListItem>
<asp:ListItem>02</asp:ListItem>
<asp:ListItem>03</asp:ListItem>
<asp:ListItem>04</asp:ListItem>
<asp:ListItem>05</asp:ListItem>
<asp:ListItem>06</asp:ListItem>
<asp:ListItem>07</asp:ListItem>
<asp:ListItem>08</asp:ListItem>
<asp:ListItem>09</asp:ListItem>
<asp:ListItem>10</asp:ListItem>
<asp:ListItem>11</asp:ListItem>
<asp:ListItem>12</asp:ListItem>
</asp:DropDownList></td>
<td></td>
<td>
<label>End Year</label></td>
<td>
<asp:DropDownList ID="ddlEndYear" runat="server" Width="100%">
</asp:DropDownList></td>
<td>
<asp:Button ID="btnLock" runat="server" Width="120px" Text="Lock" CssClass="submitButton"
BorderStyle="None" OnClick="btnLock_Click" />
</td>
<td>
<asp:Label runat="server" ID="lblLockMessage"></asp:Label>
<asp:Timer ID="Timer1" runat="server" Interval="5000" Enabled="false" OnTick="Timer1_Tick"></asp:Timer>
</td>
</tr>
</table>
</fieldset>
</div>
<div>
<table width="100%">
<tr>
<td>
<label>Lock Period Details</label>
</td>
<td align="right">
<asp:Label runat="server" ID="lblmsg"></asp:Label>
</td>
</tr>
<tr>
<td colspan="2">
<asp:GridView ID="gvLockPeriod" runat="server" AutoGenerateColumns="false" CssClass="mGrid" OnRowDeleting="gvLockPeriod_RowDeleting"
DataKeyNames="Id">
<Columns>
<asp:CommandField ShowDeleteButton="true" ControlStyle-ForeColor="darkcyan" DeleteText="Unlock"></asp:CommandField>
<asp:BoundField DataField="FromDate" HeaderText="FromDate" />
<asp:BoundField DataField="ToDate" HeaderText="ToDate" />
<asp:TemplateField HeaderText="Cost&ServiceReport">
<ItemTemplate>
<asp:ImageButton ImageUrl="~/images/Pdf-16.png" runat="server" ToolTip="Download Cost & Service Report"
Visible='<%# Convert.ToBoolean(Eval("CostServiceReport")) %>'
PostBackUrl='<%#"CreatePDF.ashx?id="+Eval("Id")+"&Report=CostServiceReport"+"&LockedFrom="+Eval("fromdate")+"&LockedTo="+Eval("todate")+""%>' />
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="ServiceReport">
<ItemTemplate>
<asp:ImageButton ImageUrl="~/images/Pdf-16.png" runat="server" ToolTip="Download Service Report"
Visible='<%# Convert.ToBoolean(Eval("ServiceReport")) %>'
PostBackUrl='<%#"CreatePDF.ashx?id="+Eval("Id")+"&Report=ServiceReport"+"&LockedFrom="+Eval("fromdate")+"&LockedTo="+Eval("todate")+""%>' />
</ItemTemplate>
</asp:TemplateField>
<asp:BoundField DataField="ModifiedBy" HeaderText="CreatedUser" />
<asp:BoundField DataField="ModifiedDate" HeaderText="CreatedDate" />
</Columns>
</asp:GridView>
</td>
</tr>
</table>
</div>
</ContentTemplate>
</asp:UpdatePanel>
<asp:UpdateProgress ID="UpdateProgress1" runat="server">
<ProgressTemplate>
<div class="overlays" />
<div style="font-weight: bold; align-content: center" class="overlayContents">
<asp:Image ID="aspImg1" runat="server" ImageUrl="~/images/ajax-loader.GIF" />
</div>
</ProgressTemplate>
</asp:UpdateProgress>
</asp:Content>
答案 0 :(得分：0)
在刷新响应后调用响应结束方法。
context.Response.Flush();
System.Web.HttpContext.Current.Response.End();