Programmatically adding watermark on PDF files in Sharepoint

This Blog will put some light on how to add watermark on PDF files from sharepoint document libraries and display selected in Iframe.

to achieve this we will be using itextsharp dll version 5.5.5.0 you can dowload it from here

steps to achieve PDFViewer with watermark
1. Create Visual Web Part name it according to your convenience

2. Add reference in your project to itextsharp dll

3. this is very important step don't forget to add itextsharp dll to GAC using gacutil or drag and drop feature

4. Now add two drop down control ,one iframe control and one submit button  in ascx page of visual webpart

first drop down will be used to bind names of document libraries
second will be used to select pdf files from selected document library

on click of submit button , Iframe will be used to display PDF file selected.

here is how ascx page looks like

<table style="width:100%; padding:2px;">

            <tr>
          <td class="auto-style1">Please select document libraries</td>
        <td class="auto-style1">
<asp:DropDownList ID="DocumentLibraries" runat="server" CssClass="auto-style2" AutoPostBack="true"  OnSelectedIndexChanged="DocumentLibraries_SelectedIndexChanged"></asp:DropDownList>
            </td>
    </tr>
    <tr>
        <td class="auto-style1">Please select PDF File to view</td>
        <td class="auto-style1">
<asp:DropDownList ID="pdffiles" runat="server" CssClass="auto-style2"></asp:DropDownList>
            </td>
    </tr>
    <tr>
        <td colspan="2">
            <asp:Button runat="server" ID="btnAggregrator" Text="Submit" onclick="btnAggregrator_Click"/>
        </td>
    </tr>

    </table>
<div>

<asp:Literal ID="l1" runat="server" ></asp:Literal>
</div>


5. In the ascx.cs file replace the page load method with below code

 protected void Page_Load(object sender, EventArgs e)
        {
            if (!Page.IsPostBack)
            {
                DocumentLibraries.Items.Clear();
                LoadDocumentLibraryDropdown();
            }
        }

6. Add new method as below

  private void LoadDocumentLibraryDropdown()
        {
                     SPWeb web = SPContext.Current.Web;
                 
                        DocumentLibraries.Items.Add("Please Select");
                        foreach (SPList libraries in web.Lists)
                        {
                            if (libraries.BaseType == SPBaseType.DocumentLibrary && libraries.BaseTemplate == SPListTemplateType.DocumentLibrary)
                            {
                                if (libraries.Title != "Form Templates" && libraries.Title != "Style Library" && libraries.Title != "Site Assets" && libraries.Title != "Site Collection Documents" && libraries.Title != "Translation Packages" && libraries.Title != "WaterMarkedDocuments")
                                {
                                    DocumentLibraries.Items.Add(libraries.Title);
                                }
                            }

                        }

7. Add the dropdown select index change as below

     protected void DocumentLibraries_SelectedIndexChanged(object sender, EventArgs e)
        {
         
                string documentLibrarySelected = DocumentLibraries.SelectedValue;
                if (documentLibrarySelected != "Please Select" && !string.IsNullOrEmpty(documentLibrarySelected))
                {

                             SPWeb web = SPContext.Current.Web;
                            SPDocumentLibrary library = (SPDocumentLibrary)web.Lists[documentLibrarySelected];
                            foreach (SPListItem files in library.Items)
                            {

                                if (files.File.Url.Contains(".pdf"))
                                {
                                    pdffiles.Items.Add(new System.Web.UI.WebControls.ListItem(files.File.Name, files.File.Url));

                                }                      
                    }              
                else
                {
                    pdffiles.Items.Clear();
                }
            }
}

8. Add Button click event

   protected void btnAggregrator_Click(object sender, EventArgs e)
        {
         
                string documentLibrarySelected = DocumentLibraries.SelectedValue;
                if (!string.IsNullOrEmpty(documentLibrarySelected))
                {
                    SPWeb web = SPContext.Current.Web;
                    SPWeb rootweb = SPContext.Current.Site.RootWeb;
                    SPList list = web.Lists[documentLibrarySelected];


                    SPFolder folder = rootweb.GetFolder(rootweb.Url + "/WaterMarkedDocuments");
                    if (folder.Exists == false)
                    {
                        rootweb.AllowUnsafeUpdates = true;
                        rootweb.Lists.Add("WaterMarkedDocuments", "library to store water arked documents", SPListTemplateType.DocumentLibrary);
                        rootweb.AllowUnsafeUpdates = false;
                        web.Update();
                        folder = rootweb.Folders["WaterMarkedDocuments"];

                    }

                    SPFile file = web.GetFile(pdffiles.SelectedValue);


                    SPUser currentUser = web.CurrentUser;
                    string watermark = null;
                    if (currentUser != null)
                        watermark = "Controlled Copy: " + SPContext.Current.Site.Url + "\\" + file.Title + "\\" + currentUser.Name + "\\" + System.DateTime.Now;

                    string url = web.Url + "/" + pdffiles.SelectedValue;

                    byte[] content = file.OpenBinary();


                    string newUrl = AddWaterMark(watermark, file, folder);


                    string modifiedUrl = rootweb.Url + "/WaterMarkedDocuments" + "/" + newUrl + "#toolbar=0&navpanes=0";

                    l1.Text = "<object id='AcrobatFrame' type='application/pdf' data='" + modifiedUrl + "' width='609' height='509'></object>";


                }
            }
9. add AddWaterMark event as below ( this method writes watermark over PDF files

 private string AddWaterMark(string watermarkText, SPFile file, SPFolder documentLibrayName)
        {
            string NewURL = string.Empty;
         
                SPFile fwatermarkfile = file;
             
                byte[] content = fwatermarkfile.OpenBinary();

                PdfReader pdfReader = new PdfReader(content);
                using (MemoryStream outputStream = new MemoryStream())
                using (PdfStamper pdfStamper = new PdfStamper(pdfReader, outputStream))
                {
                    for (int pageIndex = 1; pageIndex <= pdfReader.NumberOfPages; pageIndex++)
                    {
                        //Rectangle class in iText represent geometric representation...
                        //in this case, rectangle object would contain page geometry
                        Rectangle pageRectangle = pdfReader.GetPageSizeWithRotation(pageIndex);
                        //PdfContentByte object contains graphics and text content of page returned by PdfStamper
                        PdfContentByte pdfData = pdfStamper.GetUnderContent(pageIndex);
                        //create font size for watermark
                        pdfData.SetFontAndSize(BaseFont.CreateFont(BaseFont.HELVETICA_BOLD, BaseFont.CP1252, BaseFont.NOT_EMBEDDED), 13);
                        //create new graphics state and assign opacity
                        PdfGState graphicsState = new PdfGState();
                        graphicsState.FillOpacity = 0.4F;
                        //set graphics state to PdfContentByte
                        pdfData.SetGState(graphicsState);
                        //indicates start of writing of text
                        pdfData.BeginText();
                        //show text as per position and rotation
                        pdfData.ShowTextAligned(Element.ALIGN_CENTER, watermarkText, pageRectangle.Width / 2, pageRectangle.Height / 44, 0);
                        //call endText to invalid font set
                        pdfData.EndText();
                    }
                    pdfStamper.Close();
                    content = outputStream.ToArray();
                    SPUser user = SPContext.Current.Web.CurrentUser;
                        NewURL = "WaterMarked" + file.Name;
                      documentLibrayName.Files.Add(NewURL, content,true);
                }
         
         
         
            return NewURL;
        }
    }
}


The above webpart will not modify the original pdf file it will copy the content of selected pdf file and it will create new pdf file with watermark in document library WaterMarkedDocuments ( code takes care of creating this document library .


if u have any doubts over this article please feel free to contact me over vishalkd@gmail.com. Happy coding !!

Thread was being aborted in sharepoint custom code

Thread was being aborted is one of the common error in custom code used to build web parts or any other solutions related to sharepoint , lets look into how i resolved it

If you want user to be redirected to new page or site and u are doing it in try catch block above error will be catch always but still user will be redirected to new URL.

ex :

Code : 

 try
            {
                // custom code to perform some action
                HttpContext.Current.Response.Redirect(RedirectURL);
            }
            catch (Exception ex)
            {
                // log the error to event to custom list
            }

Solution 1 : 

so avoid error please move Response.Redirect out of try catch as shown below 

// ***  Code *** //

 try
            {
                // custom code to perform some action
             
            }
            catch (Exception ex)
            {
                // log the error to event to custom list
            }
 HttpContext.Current.Response.Redirect(RedirectURL);

Solution 2 : 

if you cannot avoid using Response.Redirect  out of try catch block then add Response.Redirect with end response parameter set as false   HttpContext.Current.Response.Redirect(RedirectURL,false);

// ***  Code *** //
 try
            {
                // custom code to perform some action
                HttpContext.Current.Response.Redirect(RedirectURL,false);
            }
            catch (Exception ex)
            {
                // log the error to event to custom list
            }



I hope your doubts are clear else comment for further clarification

Get Current User name using JQuery in sharepoint 2013

Here is the code to fetch current user name ( logged in user name ) using Jquery , this can be user on content editor webpart or list form .

things to take care before u use below code
1. download jquery-1.4.2.min.js and jquery.SPServices-0.5.7.min.js and
2. upload both the downloaded files to style library under new folder named as js.


<script language="javascript" src="../../Style Library//js/jquery-1.4.2.min.js" type="text/javascript"></script>  
<script language="javascript" src="../../Style Library/js/jquery.SPServices-0.5.7.min.js" type="text/javascript"></script>
<script type="text/javascript">
 
//to make sure above added script links are loaded on page
  $(document).ready(function() {
 
// to get formlabel control
  if (document.getElementById("formlabel") != null)
{

document.getElementById("formlabel").innerText =  $().SPServices.SPGetCurrentUser(
{fieldName:"Title",
debug:false
});
}
</script>

formlabel is html label , innertext of label is set to current logged in user name programmatically using above code.