问题
I try to create a PDF report from a datatable. One of the columns contents image. How can I extract the image from datatable and insert into PDF table? I'm using iTextShap version 5.4.2.0. Here is the code:
public void Report(DataTable dt, string output)
{
Document doc = new Document(PageSize.LETTER, 50, 50, 80, 50);
PdfWriter PDFWriter = PdfWriter.GetInstance(doc, new FileStream(output, FileMode.Create));
PDFWriter.ViewerPreferences = PdfWriter.PageModeUseOutlines;
iTextSharp.text.Font hel8 = FontFactory.GetFont(BaseFont.HELVETICA, 8);
doc.Open();
PdfPTable table = new PdfPTable(dt.Columns.Count);
float[] widths = new float[] { 1.2f, 1.2f, 1.2f, 1.2f, 1f, 4f, 1f, 4f };
table.SetWidths(widths);
table.WidthPercentage = 100;
PdfPCell cell = new PdfPCell(new Phrase("NewCells"));
cell.Colspan = dt.Columns.Count;
foreach (DataColumn c in dt.Columns)
{
table.AddCell(new Phrase(c.ColumnName, hel8));
}
foreach (DataRow r in dt.Rows)
{
if (dt.Rows.Count > 0)
{
table.AddCell(new Phrase(r[0].ToString(), hel8));
table.AddCell(new Phrase(r[1].ToString(), hel8));
table.AddCell(new Phrase(r[2].ToString(), hel8));
table.AddCell(new Phrase(r[3].ToString(), hel8));
table.AddCell(new Phrase(r[4].ToString(), hel8));
table.AddCell(new Phrase(r[5].ToString(), hel8));
byte[] byt = (byte[])r[6];
MemoryStream ms = new MemoryStream(byt);
System.Drwaing.Image sdi = System.Drawing.Image.FromStream(ms);
Image img = Image.GetInstance(sdi); <-- this is the problem code
table.AddCell(img);
table.AddCell(new Phrase(r[7].ToString(), hel8));
}
}
doc.Add(table);
}
doc.Close();
}
Update: @nekno, all of your suggestions are worked.
But I still need to correct the casting at line:
byte[] byt = (byte[])r[6];
It gave me a casting exception from VS2008. So I added the conversion function (pulled it from stackoverflow):
byte[] ImageToByte(System.Drawing.Image img)
{
byte[] byteArray = new byte[0];
using (MemoryStream stream = new MemoryStream())
{
img.Save(stream, System.Drawing.Imaging.ImageFormat.Png);
stream.Close();
byteArray = stream.ToArray();
}
return byteArray;
}
And revised the code:
byte[] byt = ImageToByte((System.Drawing.Image)dt.Rows[e][6]);
Thanks.
回答1:
What exactly is the problem? What happens when you use your problem code?
Try one of the other Image.GetInstance() overloads:
You can pass the byte array directly:
byte[] byt = (byte[])r[6];
Image img = Image.GetInstance(byt);
Or you can pass the Stream:
byte[] byt = (byte[])r[6];
MemoryStream ms = new MemoryStream(byt);
Image img = Image.GetInstance(ms);
Or you can give iTextSharp more info about the image format:
byte[] byt = (byte[])r[6];
MemoryStream ms = new MemoryStream(byt);
System.Drawing.Image sdi = System.Drawing.Image.FromStream(ms);
Image img = Image.GetInstance(sdi, ImageFormat.Png);
If your column can be cast to a System.Drawing.Image, then you can use it directly:
Image img = Image.GetInstance((System.Drawing.Image)r[6], System.Drawing.Imaging.ImageFormat.Png);
回答2:
I have suggested steps how shows how to add image into PDF, given below code snippet show how to add logo into your PDF using iTextsharp, follow provided below steps:
- I have provided link to download "itextsharp" component from given link http://sourceforge.net/projects/itextsharp/
- You have to add reference into your application.
- Next you have to add required namespaces "iTextsharp.text.html", "iTextsharp.text" to consume its best properties.
- Now you have to add code snippet into your application given at the end, add code snippet under "button click" in code behind.
Hope it will work for you !!!
protected void btnPDF_Click(object sender, ImageClickEventArgs e)
{
DataTable dtn = new DataTable();
dtn = GetDataTable();
dtPDF = dtn.Copy();
for (int i = 0; i <= dtn.Rows.Count - 1; i++)
{
ExportToPdf(dtPDF);
}
}
public void ExportToPdf(DataTable myDataTable)
{
Document pdfDoc = new Document(PageSize.A4, 10, 10, 10, 10);
try
{
PdfWriter.GetInstance(pdfDoc, System.Web.HttpContext.Current.Response.OutputStream);
pdfDoc.Open();
Chunk c = new Chunk("" + System.Web.HttpContext.Current.Session["CompanyName"] + "", FontFactory.GetFont("Verdana", 11));
Paragraph p = new Paragraph();
p.Alignment = Element.ALIGN_CENTER;
p.Add(c);
pdfDoc.Add(p);
string clientLogo = Server.MapPath(".") + "/logo/tpglogo.jpg";
string imageFilePath = Server.MapPath(".") + "/logo/tpglogo.jpg";
iTextSharp.text.Image jpg = iTextSharp.text.Image.GetInstance(imageFilePath);
//Resize image depend upon your need
jpg.ScaleToFit(80f, 60f);
//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 = myDataTable;
if (dt != null)
{
//Craete instance of the pdf table and set the number of column in that table
PdfPTable PdfTable = new PdfPTable(dt.Columns.Count);
PdfPCell PdfPCell = null;
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();
Response.ContentType = "application/pdf";
Response.AddHeader("content-disposition", "attachment; filename= SampleExport.pdf");
System.Web.HttpContext.Current.Response.Write(pdfDoc);
Response.Flush();
Response.End();
//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);
}
}
来源：https://stackoverflow.com/questions/17602038/itextsharp-add-image-to-pdf-from-datatable