I am trying to make captcha code. this is my code in model to generate captcha.
private static Random random = new Random();
public override void ExecuteResult(ControllerContext context)
{
Bitmap bmp = new Bitmap(100, 30);
Graphics g = Graphics.FromImage(bmp);
g.Clear(Color.DeepPink);
string randomString = GetCaptchaString(6);
context.HttpContext.Session["captchastring"] = randomString;
g.DrawString(randomString, new Font(FontFamily.GenericSansSerif, 17,FontStyle.Italic), new SolidBrush(Color.WhiteSmoke), 2, 2);
HttpResponseBase response = context.HttpContext.Response;
response.ContentType = "image/jpeg";
bmp.Save(response.OutputStream, ImageFormat.Jpeg);
bmp.Dispose();
}
public string GetCaptchaString(int length)
{
const string chars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
return new string(Enumerable.Repeat(chars, length)
.Select(s => s[random.Next(s.Length)]).ToArray());
}
The captcha view code is as following
#using (Html.BeginForm("index", "home"))
{
<p><img src="/home/ShowCaptchaImage" id="imgCaptchaShow" /></p>`
<p>Please enter the string as shown above:</p>`
<p>#Html.TextBox("CaptchaText")</p>Refresh`
<p><input type="submit" value="Submit" /></p>
}
I want to generate captcha again on refresh link without refreshing page.
Related
I am trying to send emails with attachments attached to the email. I have a InputFile with a progress bar that I am able to upload files. I have attempted to use the memory stream to make attachments to the MailMessage class. The issue is that when the email is received, I am able to see the attachments but I can't read or view the contents of the attachments. I've posted my code below so you can replicate the issue that I am having (Make sure to install the Meziantou.Framework.ByteSize nuget package)
#using System.Net.Mail
#using System.Globalization
#using Meziantou.Framework
<InputFile OnChange="e => LoadFiles(e)" multiple></InputFile>
#foreach (var file in uploadedFiles)
{
<div>
#file.FileName
<progress value="#file.UploadedBytes" max="#file.Size"></progress>
#file.UploadedPercentage.ToString("F1")%
(#FormatBytes(file.UploadedBytes) / #FormatBytes(file.Size))
</div>
}
<button type="button" #onclick="#HandleNotifSubmit" class="btn btn-primary submit">Send Email</button>
#code {
private MemoryStream fileContents { get; set; }
List<FileUploadProgress> uploadedFiles = new();
MailMessage message = new MailMessage();
StreamWriter writer { get; set; }
private async ValueTask LoadFiles(InputFileChangeEventArgs e)
{
var files = e.GetMultipleFiles(maximumFileCount: 100);
var startIndex = uploadedFiles.Count;
// Add all files to the UI
foreach (var file in files)
{
var progress = new FileUploadProgress(file.Name, file.Size);
uploadedFiles.Add(progress);
}
// We don't want to refresh the UI too frequently,
// So, we use a timer to update the UI every few hundred milliseconds
await using var timer = new Timer(_ => InvokeAsync(() => StateHasChanged()));
timer.Change(TimeSpan.FromMilliseconds(500), TimeSpan.FromMilliseconds(500));
// Upload files
byte[] buffer = System.Buffers.ArrayPool<byte>.Shared.Rent(4096);
try
{
foreach (var file in files)
{
using var stream = file.OpenReadStream(maxAllowedSize: 10 * 1024 * 1024);
while (await stream.ReadAsync(buffer) is int read && read > 0)
{
uploadedFiles[startIndex].UploadedBytes += read;
var readData = buffer.AsMemory().Slice(0, read);
}
fileContents = new MemoryStream(buffer);
writer = new StreamWriter(fileContents);
fileContents.Position = 0;
message.Attachments.Add(new Attachment(fileContents, file.Name));
startIndex++;
}
}
finally
{
System.Buffers.ArrayPool<byte>.Shared.Return(buffer);
StateHasChanged();
}
}
string FormatBytes(long value)
=> ByteSize.FromBytes(value).ToString("fi2", CultureInfo.CurrentCulture);
record FileUploadProgress(string FileName, long Size)
{
public long UploadedBytes { get; set; }
public double UploadedPercentage => (double)UploadedBytes / (double)Size * 100d;
}
private async void HandleNotifSubmit()
{
try
{
var sClient = new SmtpClient("FAKECOMPANYCLIENT");
sClient.Port = 25;
sClient.UseDefaultCredentials = false;
message.Subject = "Hello World";
message.From = new MailAddress("test#gmail.com");
message.IsBodyHtml = true;
message.To.Add(new MailAddress("Fake#gmail.com"));
message.Body = "Please view attachments below.";
sClient.Send(message);
message.Dispose();
}
catch
{
Console.WriteLine("error");
}
}
}
I have also tried to use a stream writer with no success. I have also tried various ways to do a file.CopyToAsync(memoryStreamname). I am not sure what else I am missing or doing wrong here.
Thank you in advance.
I have a middleware which calculates Razor Page execution time:
app.Use(async (context, next) =>
{
var sw = new Stopwatch();
sw.Start();
await next.Invoke();
sw.Stop();
await context.Response.WriteAsync($"<div class=\"container\">Processing time: {sw.ElapsedMilliseconds} ms<div>");
});
It works fine, however HTML created by WriteAsync is added at the very end of the response, after closing </html> tag.
How can I place - pass or inject - a value of sw.ElapsedMilliseconds calculated by the middleware in specific place inside HTML body? Using ASP.NET Core 6.0.
Maybe you can use the HTML Agility Pack.
You can use the LoadHtml and HtmlNode.CreateNode methods to create the html element you want to insert, and then use DocumentNode.SelectSingleNode to select the position you want to insert.
For testing,you can refer to the following code:
Custom middleware:
//Install-Package HtmlAgilityPack
public class ResponseMeasurementMiddleware
{
private readonly RequestDelegate _next;
public ResponseMeasurementMiddleware(RequestDelegate next)
{
_next = next;
}
public async Task Invoke(HttpContext context)
{
var originalBody = context.Response.Body;
var newBody = new MemoryStream();
context.Response.Body = newBody;
var watch = new Stopwatch();
long responseTime = 0;
watch.Start();
await _next(context);
// read the new body
responseTime = watch.ElapsedMilliseconds;
newBody.Position = 0;
var newContent = await new StreamReader(newBody).ReadToEndAsync();
// calculate the updated html
var updatedHtml = CreateDataNode(newContent, responseTime);
// set the body = updated html
var updatedStream = GenerateStreamFromString(updatedHtml);
await updatedStream.CopyToAsync(originalBody);
context.Response.Body = originalBody;
}
public static Stream GenerateStreamFromString(string s)
{
var stream = new MemoryStream();
var writer = new StreamWriter(stream);
writer.Write(s);
writer.Flush();
stream.Position = 0;
return stream;
}
private string CreateDataNode(string originalHtml, long responseTime)
{
var htmlDoc = new HtmlDocument();
htmlDoc.LoadHtml(originalHtml);
HtmlNode testNode = HtmlNode.CreateNode($"<div class=\"container\">Processing time: {responseTime.ToString()} ms.</div>");
var htmlBody = htmlDoc.DocumentNode.SelectSingleNode(".//body/div");
if (htmlBody != null)
{
htmlBody.InsertBefore(testNode, htmlBody.FirstChild);
}
string rawHtml = htmlDoc.DocumentNode.OuterHtml; //using this results in a page that displays my inserted HTML correctly, but duplicates the original page content.
//rawHtml = "some text"; uncommenting this results in a page with the correct format: this text, followed by the original contents of the page
return rawHtml;
}
}
htmlDoc.DocumentNode.SelectSingleNode(".//body/div") and htmlBody.InsertBefore(testNode, htmlBody.FirstChild) can customize where you want to insert.
And use custom middleware:
app.UseMiddleware<ResponseMeasurementMiddleware>();
Test Result:
I'm trying to convert HTML to PDF using iTextSharp in an ASP.NET web application that uses both MVC, and web forms. The <img> and <a> elements have absolute and relative URLs, and some of the <img> elements are base64. Typical answers here at SO and Google search results use generic HTML to PDF code with XMLWorkerHelper that looks something like this:
using (var stringReader = new StringReader(xHtml))
{
using (Document document = new Document())
{
PdfWriter writer = PdfWriter.GetInstance(document, stream);
document.Open();
XMLWorkerHelper.GetInstance().ParseXHtml(
writer, document, stringReader
);
}
}
So with sample HTML like this:
<div>
<h3>HTML Works, but Broken in Converted PDF</h3>
<div>Relative local <img>: <img src='./../content/images/kuujinbo_320-30.gif' /></div>
<div>
Base64 <img>:
<img src='data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAUAAAAFCAYAAACNbyblAAAAHElEQVQI12P4//8/w38GIAXDIBKE0DHxgljNBAAO9TXL0Y4OHwAAAABJRU5ErkJggg==' />
</div>
<div><a href='/somePage.html'>Relative local hyperlink, broken in PDF</a></div>
<div>
The resulting PDF: (1) is missing all images, and (2) all hyperlink(s) with relative URLs are broken and use a file URI scheme (file///XXX...) instead of pointing to the correct web site.
Some answers here at SO and others from Google search recommend replacing relative URLs with absolute URLs, which is perfectly acceptable for one-off cases. However, globally replacing all <img src> and <a href> attributes with a hard-coded string is unacceptable for this question, so please do not post an answer like that, because it will accordingly be downvoted.
Am looking for a solution that works for many different web applications residing in test, development, and production environments.
Out of the box XMLWorker only understands absolute URIs, so the described issues are expected behavior. The parser can't automagically deduce URI schemes or paths without some additional information.
Implementing an ILinkProvider fixes the broken hyperlink problem, and implementing an IImageProvider fixes the broken image problem. Since both implementations must perform URI resolution, that's the first step. The following helper class does that, and also tries to make web (ASP.NET) context calls (examples follow) as simple as possible:
// resolve URIs for LinkProvider & ImageProvider
public class UriHelper
{
/* IsLocal; when running in web context:
* [1] give LinkProvider http[s] scheme; see CreateBase(string baseUri)
* [2] give ImageProvider relative path starting with '/' - see:
* Join(string relativeUri)
*/
public bool IsLocal { get; set; }
public HttpContext HttpContext { get; private set; }
public Uri BaseUri { get; private set; }
public UriHelper(string baseUri) : this(baseUri, true) {}
public UriHelper(string baseUri, bool isLocal)
{
IsLocal = isLocal;
HttpContext = HttpContext.Current;
BaseUri = CreateBase(baseUri);
}
/* get URI for IImageProvider to instantiate iTextSharp.text.Image for
* each <img> element in the HTML.
*/
public string Combine(string relativeUri)
{
/* when running in a web context, the HTML is coming from a MVC view
* or web form, so convert the incoming URI to a **local** path
*/
if (HttpContext != null && !BaseUri.IsAbsoluteUri && IsLocal)
{
return HttpContext.Server.MapPath(
// Combine() checks directory traversal exploits
VirtualPathUtility.Combine(BaseUri.ToString(), relativeUri)
);
}
return BaseUri.Scheme == Uri.UriSchemeFile
? Path.Combine(BaseUri.LocalPath, relativeUri)
// for this example we're assuming URI.Scheme is http[s]
: new Uri(BaseUri, relativeUri).AbsoluteUri;
}
private Uri CreateBase(string baseUri)
{
if (HttpContext != null)
{ // running on a web server; need to update original value
var req = HttpContext.Request;
baseUri = IsLocal
// IImageProvider; absolute virtual path (starts with '/')
// used to convert to local file system path. see:
// Combine(string relativeUri)
? req.ApplicationPath
// ILinkProvider; absolute http[s] URI scheme
: req.Url.GetLeftPart(UriPartial.Authority)
+ HttpContext.Request.ApplicationPath;
}
Uri uri;
if (Uri.TryCreate(baseUri, UriKind.RelativeOrAbsolute, out uri)) return uri;
throw new InvalidOperationException("cannot create a valid BaseUri");
}
}
Implementing ILinkProvider is pretty simple now that UriHelper gives the base URI. We just need the correct URI scheme (file or http[s]):
// make hyperlinks with relative URLs absolute
public class LinkProvider : ILinkProvider
{
// rfc1738 - file URI scheme section 3.10
public const char SEPARATOR = '/';
public string BaseUrl { get; private set; }
public LinkProvider(UriHelper uriHelper)
{
var uri = uriHelper.BaseUri;
/* simplified implementation that only takes into account:
* Uri.UriSchemeFile || Uri.UriSchemeHttp || Uri.UriSchemeHttps
*/
BaseUrl = uri.Scheme == Uri.UriSchemeFile
// need trailing separator or file paths break
? uri.AbsoluteUri.TrimEnd(SEPARATOR) + SEPARATOR
// assumes Uri.UriSchemeHttp || Uri.UriSchemeHttps
: BaseUrl = uri.AbsoluteUri;
}
public string GetLinkRoot()
{
return BaseUrl;
}
}
IImageProvider only requires implementing a single method, Retrieve(string src), but Store(string src, Image img) is easy - note inline comments there and for GetImageRootPath():
// handle <img> elements in HTML
public class ImageProvider : IImageProvider
{
private UriHelper _uriHelper;
// see Store(string src, Image img)
private Dictionary<string, Image> _imageCache =
new Dictionary<string, Image>();
public virtual float ScalePercent { get; set; }
public virtual Regex Base64 { get; set; }
public ImageProvider(UriHelper uriHelper) : this(uriHelper, 67f) { }
// hard-coded based on general past experience ^^^
// but call the overload to supply your own
public ImageProvider(UriHelper uriHelper, float scalePercent)
{
_uriHelper = uriHelper;
ScalePercent = scalePercent;
Base64 = new Regex( // rfc2045, section 6.8 (alphabet/padding)
#"^data:image/[^;]+;base64,(?<data>[a-z0-9+/]+={0,2})$",
RegexOptions.Compiled | RegexOptions.IgnoreCase
);
}
public virtual Image ScaleImage(Image img)
{
img.ScalePercent(ScalePercent);
return img;
}
public virtual Image Retrieve(string src)
{
if (_imageCache.ContainsKey(src)) return _imageCache[src];
try
{
if (Regex.IsMatch(src, "^https?://", RegexOptions.IgnoreCase))
{
return ScaleImage(Image.GetInstance(src));
}
Match match;
if ((match = Base64.Match(src)).Length > 0)
{
return ScaleImage(Image.GetInstance(
Convert.FromBase64String(match.Groups["data"].Value)
));
}
var imgPath = _uriHelper.Combine(src);
return ScaleImage(Image.GetInstance(imgPath));
}
// not implemented to keep the SO answer (relatively) short
catch (BadElementException ex) { return null; }
catch (IOException ex) { return null; }
catch (Exception ex) { return null; }
}
/*
* always called after Retrieve(string src):
* [1] cache any duplicate <img> in the HTML source so the image bytes
* are only written to the PDF **once**, which reduces the
* resulting file size.
* [2] the cache can also **potentially** save network IO if you're
* running the parser in a loop, since Image.GetInstance() creates
* a WebRequest when an image resides on a remote server. couldn't
* find a CachePolicy in the source code
*/
public virtual void Store(string src, Image img)
{
if (!_imageCache.ContainsKey(src)) _imageCache.Add(src, img);
}
/* XMLWorker documentation for ImageProvider recommends implementing
* GetImageRootPath():
*
* http://demo.itextsupport.com/xmlworker/itextdoc/flatsite.html#itextdoc-menu-10
*
* but a quick run through the debugger never hits the breakpoint, so
* not sure if I'm missing something, or something has changed internally
* with XMLWorker....
*/
public virtual string GetImageRootPath() { return null; }
public virtual void Reset() { }
}
Based on the XML Worker documentation it's pretty straightforward to hook the implementations of ILinkProvider and IImageProvider above into a simple parser class:
/* a simple parser that uses XMLWorker and XMLParser to handle converting
* (most) images and hyperlinks internally
*/
public class SimpleParser
{
public virtual ILinkProvider LinkProvider { get; set; }
public virtual IImageProvider ImageProvider { get; set; }
public virtual HtmlPipelineContext HtmlPipelineContext { get; set; }
public virtual ITagProcessorFactory TagProcessorFactory { get; set; }
public virtual ICSSResolver CssResolver { get; set; }
/* overloads simplfied to keep SO answer (relatively) short. if needed
* set LinkProvider/ImageProvider after instantiating SimpleParser()
* to override the defaults (e.g. ImageProvider.ScalePercent)
*/
public SimpleParser() : this(null) { }
public SimpleParser(string baseUri)
{
LinkProvider = new LinkProvider(new UriHelper(baseUri, false));
ImageProvider = new ImageProvider(new UriHelper(baseUri, true));
HtmlPipelineContext = new HtmlPipelineContext(null);
// another story altogether, and not implemented for simplicity
TagProcessorFactory = Tags.GetHtmlTagProcessorFactory();
CssResolver = XMLWorkerHelper.GetInstance().GetDefaultCssResolver(true);
}
/*
* when sending XHR via any of the popular JavaScript frameworks,
* <img> tags are **NOT** always closed, which results in the
* infamous iTextSharp.tool.xml.exceptions.RuntimeWorkerException:
* 'Invalid nested tag a found, expected closing tag img.' a simple
* workaround.
*/
public virtual string SimpleAjaxImgFix(string xHtml)
{
return Regex.Replace(
xHtml,
"(?<image><img[^>]+)(?<=[^/])>",
new MatchEvaluator(match => match.Groups["image"].Value + " />"),
RegexOptions.IgnoreCase | RegexOptions.Multiline
);
}
public virtual void Parse(Stream stream, string xHtml)
{
xHtml = SimpleAjaxImgFix(xHtml);
using (var stringReader = new StringReader(xHtml))
{
using (Document document = new Document())
{
PdfWriter writer = PdfWriter.GetInstance(document, stream);
document.Open();
HtmlPipelineContext
.SetTagFactory(Tags.GetHtmlTagProcessorFactory())
.SetLinkProvider(LinkProvider)
.SetImageProvider(ImageProvider)
;
var pdfWriterPipeline = new PdfWriterPipeline(document, writer);
var htmlPipeline = new HtmlPipeline(HtmlPipelineContext, pdfWriterPipeline);
var cssResolverPipeline = new CssResolverPipeline(CssResolver, htmlPipeline);
XMLWorker worker = new XMLWorker(cssResolverPipeline, true);
XMLParser parser = new XMLParser(worker);
parser.Parse(stringReader);
}
}
}
}
As commented inline, SimpleAjaxImgFix(string xHtml) specifically handles XHR that may send unclosed <img> tags, which is valid HTML, but invalid XML that will break XMLWorker . A simple explanation & implementation of how to receive a PDF or other binary data with XHR and iTextSharp can be found here.
A Regex was used in SimpleAjaxImgFix(string xHtml) so that anyone using (copy/paste?) the code doesn't need to add another nuget package, but a HTML parser like HtmlAgilityPack should be used, since it's turns this:
<div><img src='a.gif'><br><hr></div>
into this:
<div><img src='a.gif' /><br /><hr /></div>
with only a few lines of code:
var hDocument = new HtmlDocument()
{
OptionWriteEmptyNodes = true,
OptionAutoCloseOnEnd = true
};
hDocument.LoadHtml("<div><img src='a.gif'><br><hr></div>");
var closedTags = hDocument.DocumentNode.WriteTo();
Also of note - use SimpleParser.Parse() above as a general blueprint to additionally implement a custom ICSSResolver or ITagProcessorFactory, which is explained in the documentation.
Now the issues described in the question should be taken care of. Called from a MVC Action Method:
[HttpPost] // some browsers have URL length limits
[ValidateInput(false)] // or throws HttpRequestValidationException
public ActionResult Index(string xHtml)
{
Response.ContentType = "application/pdf";
Response.AppendHeader(
"Content-Disposition", "attachment; filename=test.pdf"
);
var simpleParser = new SimpleParser();
simpleParser.Parse(Response.OutputStream, xHtml);
return new EmptyResult();
}
or from a Web Form that gets HTML from a server control:
Response.ContentType = "application/pdf";
Response.AppendHeader("Content-Disposition", "attachment; filename=test.pdf");
using (var stringWriter = new StringWriter())
{
using (var htmlWriter = new HtmlTextWriter(stringWriter))
{
ConvertControlToPdf.RenderControl(htmlWriter);
}
var simpleParser = new SimpleParser();
simpleParser.Parse(Response.OutputStream, stringWriter.ToString());
}
Response.End();
or a simple HTML file with hyperlinks and images on the file system:
<h1>HTML Page 00 on Local File System</h1>
<div>
<div>
Relative <img>: <img src='Images/alt-gravatar.png' />
</div>
<div>
Hyperlink to file system HTML page:
<a href='file-system-html-01.html'>Page 01</a>
</div>
</div>
or HTML from a remote web site:
<div>
<div>
<img width="200" alt="Wikipedia Logo"
src="portal/wikipedia.org/assets/img/Wikipedia-logo-v2.png">
</div>
<div lang="en">
English
</div>
<div lang="en">
iText
</div>
</div>
Above two HTML snippets run from a console app:
var filePaths = Path.Combine(basePath, "file-system-html-00.html");
var htmlFile = File.ReadAllText(filePaths);
var remoteUrl = Path.Combine(basePath, "wikipedia.html");
var htmlRemote = File.ReadAllText(remoteUrl);
var outputFile = Path.Combine(basePath, "filePaths.pdf");
var outputRemote = Path.Combine(basePath, "remoteUrl.pdf");
using (var stream = new FileStream(outputFile, FileMode.Create))
{
var simpleParser = new SimpleParser(basePath);
simpleParser.Parse(stream, htmlFile);
}
using (var stream = new FileStream(outputRemote, FileMode.Create))
{
var simpleParser = new SimpleParser("https://wikipedia.org");
simpleParser.Parse(stream, htmlRemote);
}
Quite a long answer, but taking a look at questions here at SO tagged html, pdf, and itextsharp, as of this writing (2016-02-23) there are 776 results against 4,063 total tagged itextsharp - that's 19%.
Very helpful post,
I was problem to render images in my report html to pdf. with your post I could do it.
I'm working with asp.mvc 5.
I only have to change this method of the ImageProviderClass
public virtual string GetImageRootPath() { return null; }
to
public virtual string GetImageRootPath() { HostingEnvironment.MapPath("~/Content/Images/") }
thanks!
Anyone can help in this code, the pdf file is not loading in app and just showing blank white screen, Logcat showing FileNotFoundExeeption: /storage/sdcard/raw/ourpdf.pdf.
i am trying to make an app that will show information while i click buttons and every button will be active for specific pdf file reading. Any specific help please.
Thanks for help
part1
package com.code.androidpdf;
public class MainActivity extends Activity {
//Globals:
private WebView wv;
private int ViewSize = 0;
//OnCreate Method:
#Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//Settings
PDFImage.sShowImages = true; // show images
PDFPaint.s_doAntiAlias = true; // make text smooth
HardReference.sKeepCaches = true; // save images in cache
//Setup above
wv = (WebView)findViewById(R.id.webView1);
wv.getSettings().setBuiltInZoomControls(true);//show zoom buttons
wv.getSettings().setSupportZoom(true);//allow zoom
//get the width of the webview
wv.getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener()
{
#Override
public void onGlobalLayout()
{
ViewSize = wv.getWidth();
wv.getViewTreeObserver().removeGlobalOnLayoutListener(this);
}
});
pdfLoadImages();//load images
}
private void pdfLoadImages() {
try
{
// run async
new AsyncTask<Void, Void, Void>()
{
// create and show a progress dialog
ProgressDialog progressDialog = ProgressDialog.show(MainActivity.this, "", "Opening...");
#Override
protected void onPostExecute(Void result)
{
//after async close progress dialog
progressDialog.dismiss();
}
#Override
protected Void doInBackground(Void... params)
{
try
{
// select a document and get bytes
File file = new File(Environment.getExternalStorageDirectory().getPath()+"/randompdf.pdf");
RandomAccessFile raf = new RandomAccessFile(file, "r");
FileChannel channel = raf.getChannel();
net.sf.andpdf.nio.ByteBuffer bb = null ;
raf.close();
// create a pdf doc
PDFFile pdf = new PDFFile(bb);
//Get the first page from the pdf doc
PDFPage PDFpage = pdf.getPage(1, true);
//create a scaling value according to the WebView Width
final float scale = ViewSize / PDFpage.getWidth() * 0.95f;
//convert the page into a bitmap with a scaling value
Bitmap page = PDFpage.getImage((int)(PDFpage.getWidth() * scale), (int)(PDFpage.getHeight() * scale), null, true, true);
//save the bitmap to a byte array
ByteArrayOutputStream stream = new ByteArrayOutputStream();
page.compress(Bitmap.CompressFormat.PNG, 100, stream);
stream.close();
byte[] byteArray = stream.toByteArray();
//convert the byte array to a base64 string
String base64 = Base64.encodeToString(byteArray, Base64.DEFAULT);
//create the html + add the first image to the html
String html = "<!DOCTYPE html><html><body bgcolor=\"#7f7f7f\"><img src=\"data:image/png;base64,"+base64+"\" hspace=10 vspace=10><br>";
//loop through the rest of the pages and repeat the above
for(int i = 2; i <= pdf.getNumPages(); i++)
{
PDFpage = pdf.getPage(i, true);
page = PDFpage.getImage((int)(PDFpage.getWidth() * scale), (int)(PDFpage.getHeight() * scale), null, true, true);
stream = new ByteArrayOutputStream();
page.compress(Bitmap.CompressFormat.PNG, 100, stream);
stream.close();
byteArray = stream.toByteArray();
base64 = Base64.encodeToString(byteArray, Base64.DEFAULT);
html += "<img src=\"data:image/png;base64,"+base64+"\" hspace=10 vspace=10><br>";
}
html += "</body></html>";
//load the html in the webview
wv.loadDataWithBaseURL("", html, "text/html","UTF-8", "");
}
catch (Exception e)
{
Log.d("CounterA", e.toString());
}
return null;
}
}.execute();
System.gc();// run GC
}
catch (Exception e)
{
Log.d("error", e.toString());
}
}
}
It is (sadly) not possible to view a PDF that is stored locally in your devices. Android L has introduced the feature. So, to display a PDF , you have two options:
See this answer for using webview
How to open local pdf file in webview in android? (note that this requires an internet connection)
Use a third party pdf Viewer.
You can also send an intent for other apps to handle your pdf.
You can get an InputStream for the file using
getResources().openRawResource(R.raw.ourpdf)
Docs: http://developer.android.com/reference/android/content/res/Resources.html#openRawResource(int)
I've used a custom control (HTML Helper) to build an Autocomplete controller.
it works great, the only thing is the validation problem.
on the client side, the validation works fine when jquery.validation.js is out of the picture, (for empty text box it gives an error message).
if the user selects something from the autocomplete, so im fine.
but when the user input is just junk, then the HttpPost needs to handle the junk & return an error message to the user.
HOW??
also, i've seen a DataAnnotation called Remote, which can manage the validation on the client side, is it better ? if so, how can i add DataAnnotaion on a custom control ??
Thank's :)
here is my code:
Index.cshtml
#using (Html.BeginForm("Index", "Create"))
{
#Html.AutocompleteFor(Url.Action("AutoCompleteServiceProviders", "Create"), true, "ex. Shower", c => c.service_id, a => a.name)
<input type="submit" id="search" value="" />
}
AutoComplete.cs
private static MvcHtmlString CreateAutocomplete<TModel>(this HtmlHelper<TModel> helper, string actionUrl, bool? isRequired, string placeholder, params Expression<Func<TModel, object>>[] expression)
{
var builder = new StringBuilder();
foreach (var item in expression)
{
var attributes = new Dictionary<string, object>
{
{ "data-autocomplete", true },
{ "data-action", actionUrl }
};
if (!string.IsNullOrWhiteSpace(placeholder))
{
attributes.Add("placeholder", placeholder);
}
if (isRequired.HasValue && isRequired.Value)
{
attributes.Add("required", "required");
}
Func<TModel, object> method = item.Compile();
var value = (Object)null;
if ((TModel)helper.ViewData.Model != null)
{
value = method((TModel)helper.ViewData.Model);
}
var baseProperty = (string)null;
var hidden = (MvcHtmlString)null;
if (item.Body is MemberExpression)
{
baseProperty = ((MemberExpression)item.Body).Member.Name;
hidden = helper.Hidden(baseProperty, value);
attributes.Add("data-value-name", baseProperty);
}
else
{
var op = ((UnaryExpression)item.Body).Operand;
baseProperty = ((MemberExpression)op).Member.Name;
hidden = helper.Hidden(baseProperty, value);
}
attributes.Add("data-value-id", "service_id");
var automcompleteName = baseProperty + "_autocomplete";
var textBox = (MvcHtmlString)null;
if (value != null)
{
textBox = helper.TextBox(automcompleteName, value, string.Empty, attributes);
}
else
{
textBox = helper.TextBox(automcompleteName, null, string.Empty, attributes);
}
builder.AppendLine(hidden.ToHtmlString());
if (baseProperty == "name")
{
builder.AppendLine(textBox.ToHtmlString());
}
}
return new MvcHtmlString(builder.ToString());
}
You can get your validation from here:
var validation = htmlHelper.ValidationMessageFor(expression, null, new Dictionary<string, object>());
UPDATE:
I use TagBuilder to create tags. What I do with tagbuilder is add that validation to a span or div tag and let the unobtrusive javascript hide/show it when needed. It returns an MVCHtmlString you can just append it to the element you want to display it in