Download and upload images with ASP.net - asp.net

In my web application, I need to be able to allow users to upload and download their images. How can this be don in ASP.net?
I want to user to be able to sign in (I already have that done) and be able to upload images to their account. Later on, I want them to be able to download them.
Thanks

If the images are of a reasonable size, (e.g. less than a few MB), you can do this with a <input type=file> tag. Set the encoding of your form tag to multipart/form-data and implement some code-behind to get a hold of the file.
See the ASP.Net videos (Part 1) and (Part 2) for a detailed example.
Hope this helps!

You can also use
<asp:FileUpload runat="server" id="upImage" Width="575px" CssClass="txt-Normal"></asp:FileUpload>
Here is my method to save them to a location on the site.
string completeFilePath = this.Request.PhysicalApplicationPath + System.Configuration.ConfigurationManager.AppSettings["ImageUploadPath"];
if (System.IO.Directory.Exists(completeFilePath))
{
System.IO.Directory.CreateDirectory(completeFilePath);
}
if (!System.IO.File.Exists(completeFilePath + this.upImage.FileName))
{
this.upImage.SaveAs(completeFilePath + this.upImage.FileName);
}
imageUrl = string.Format("~{0}{1}", System.Configuration.ConfigurationManager.AppSettings["ImageUploadPath"], this.upImage.FileName);

Related

How to take image source from code behind after updating it from client side

I have the following scenario.
User is trying to update the profile image , I am using uploadify plugin to upload image to server , and in callback I am setting
<img src="" runat="server" class="user-image" id="uploadedImage" />
SRC attribute to the uploaded path. This part is working good , then when user clicks on Save button , i need somehow to get new picture path and save it to database.
user.ImageUrl = this.uploadedImage.Attributes["src"];
doen't brings a new picture path , and returns a previous path.
Can someone help pls ?
If you want to accomplish this you may use using hidden field, among other ways.
Please refer to: http://www.codeproject.com/Articles/603102/Persist-JavaScript-changes-on-postback,http://forums.asp.net/t/1428896.aspx/1,http://forums.asp.net/t/1285473.aspx.

Where to store and how to remove images in a photo gallery?

I'm working on a photo gallery using ASP.NET.
I'm storing user's images in a SQL database. I'm not sure how should displaying images look like.
Let's say there is 1 picture per user, I was doing something like that:
get image from database
save it on server's disc as "file.jpg"
ASP:Image.uri = "file.jpg"
And that worked fine until I found out that If few users loads that page at the very same time, It might not work properly.
Then I though changing "file.jpg" into some random string would help me:
get image from database
save it on server's disc as "ABCDUDHDJSAKFHADGJKHAKADFAD.jpg"
ASP:Image.uri = "ABCDUDHDJSAKFHADGJKHAKADFAD.jpg"
File.Delete("~/ABCDUDHDJSAKFHADGJKHAKADFAD.jpg");
But it wasnt possible to delete this file because it was still being used by a server.
What would be the proper way to solve my problem? User in my photo gallery will eventually see 12 photos at the same time.
What I usually do is serve images from DB using a generic handler (ashx file).
What you need to do is create an ashx file and use something along these lines:
context.Response.BinaryWrite(myImage);
The you create image tags like so:
<img alt="whatever" src="/images.ashx?iid=1243 />
Where iid is the unique ID of the image in the DB.
You should not store the file actually. You should stream it. For example create a handler which returns the image from an user with a specific ID and call it with that ID like image.ashx?id=1. The handler could look like
Image image; // image from your database
using(MemoryStream ms = new MemoryStream())
{
image.Save(ms, System.Drawing.Imaging.ImageFormat.Png);
ms.WriteTo(context.Response.OutputStream);
}
Response.ContentType = "image/png";
This handler you can use like a static image file. So, you might even use it for a background-image:
<div style="background-image: url(image.ashx?id=1)">Username</div>

Set background-url css property to a memory image in .net

Please read about my following situation. So we have a web application in .net. Because some customers wanted to pay for some custom layout, we first started to use themes. It was ok until there were more than 10. Because after that it was difficult to maintain and more of them wanted custom design, I had to design a solution so that the user could change only a few css attributes through a front-end page.
So when a user clicked a button a folder with its name and another css file was generated and he could change the attributes and save the new file. This file was dynamically loaded on the Page_Load on some basebage. This was ok, until more and more users payed for this and now we have tens of folders and expect hundreds. There is also the problem of rights, by default IIS doesn't have writing right to the application folder. Also the deployment process builds a new version by deleting the whole app folder and recreating one so we had to do a workaround and make a copy of this mega folder that holds the users css. And anyway, I don't like the idea of having hundreds of files not under source control.
And now, I have a new requierement. The users to be allowed to upload a custom image to replace one of our own. So i said it is time to move evrything to the database. For basic attributes I solved it.
I have a "mutant" aspx page:
<%# Page Language="C#" ContentType="text/css" %>
.labelText
{
color:<%= WebApplication1.UserProfile.LabelColor%>
}
So the UserProfile class gets it's data from a table.
And then in the page_load of the basepage
HtmlLink link = new HtmlLink();
link.Attributes.Add("type", "text/css");
link.Attributes.Add("rel", "stylesheet");
link.Attributes.Add("href", "~/Styles/Override.aspx");
this.Header.Controls.Add(link);
It works ok, the problem the images are used like this:
.divHeader
{
background: 15px 0 url("logo.gif")
}
That logo.gig will be uploaded by the user,but I would like to be saved in the database. However when reading it as a stream I can't do something like:
background: 15px 0 url(WebApplication1.UserProfile.Logo)
Is there any otehr way I can specify an object in a css class?If it isn't what is the best approach? I was thinking about keeping the image in the db and also as a file, something similar to what we have now.
I realize that if it were for an image control it would have been a lot easier, but this is the design now, and remaking it is a little bit troublesome
Thanks for reading this novel and for any oppinions on this.
I hope you're saving the mime-type value of every image that you save to database (mime type is reported by the request during upload). If you don't, you'll have to look up what a mime type would be based on image-file extension or its content format. You'll need this value when images are requested (from within CSS files).
Implement an HTTP handler (.ashx) specifically for these images (new file > generic handler > fill up ProcessRequest).
Then, replace url(logo.gif) in your css files with something like this:
url(/GetImage.ashx?user=1234&image=logo);
Obviously, you can have the filename and query to be whatever you like/need. Maybe you have user info in session, so you don't have to include user id there. Maybe you'll want to implement this handler only for logo images, and if you have user info in session, you can simply say (css):
url(GetLogo.ashx);
Then, within that ashx handler, write code to get the image from the database (or where ever it is), and stream it to the browser. Something like this:
byte[] imageData = ... // get this from db
MemoryStream ms = new MemoryStream(imageData); // System.IO namespace
Response.ContentType = "image/png"; // remember the mime-type?
ms.WriteTo(context.Response.OutputStream); // context is current HttpContext
Alternatively, you can inject the whole image into the CSS, by encoding it to base-64 format. Note that the size of css file will grow for the size of the image, and you're practically combining multiple downloads into 1, which may be a good or a bad thing.
Example below (google's logo); paste this in CSS (notice the size of that thing).
Besides CSS, the data in this example (data:image/png;base64,iVBORw0KGg ...) can be used as URL with IMG tags, or manipulated by JS.
.somediv
{
width:275px;
height:95px;
background-image: url(data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAARMAAABfCAMAAAD8mtMpAAAC/VBMVEUBIrIZH6qfBSGwAyWSDiTEAym9DifSCyysGCiQISvJES3eDDLMFinYGDDdFyzkGjbmGzGhMTePNjwsSa3JKDQYTukOZh3iKDKKQUPvKzHwKjnoLUDFODyxQUTAQEPuNT3kOEDeO0anS0xJYKH2OTf0Oz6fVVY5aN3zRErSXAD3SkflUE2cZmTgU1tGg1DAYV32U1HXXVyVcG60aGO1cSLOcAKfeEncbgD4YVaugED5Z1+1enfNfxGqf3x5ibPjfACgh168hTKXi3nJfHuih4WdjXP5dGnJih7mhQDvenOKla2ck5Bcqm7wjwDnkQhxne++llbfiYa6m1/JmkHyioDwmQDZnSe+nZnnoA7Wmpb6nwDyoQy+p3jTqUa5qpD5pgDoqB+5q6v4npH/rgCps834rxD/tADiuDvWs7D+uQ3/wCLiwXTPwqSZ1az+xjWw0rvjyYrg0K722YvH6tL35bX98tT99uEAQOKlpqNIh/03dPsAVP1UivYqSvC7vLnn6ebr7ert8Pjw8+8iYvojXvr19/P5+/j3+/4aReoAR/Gwsq50f5sMrBcAsBgvbvwGtCGkvvYSTfgANtvGx8QCLMLP0M0AS+3W2NV9qPnQ3Pnd39zY4PY0Wcf529fj5OErZu4yZPIjaPwbPOI8ff0AS/VGascSV/mNsvgAL8yYm5f///9ZcrKUlZstV9NueZ778vFfcacaMdHwrqcYPdABN9THyM8IdwW/y+domfj608cpUdQiUt8jSOZjdKBaie3x5cQHjhg1a+336OVvh8UAgQzxo56xtcUQML9Marmcu/mAoeUAkw4jljYJQe2kvOv+zETk6fm5z/ogUfUZVuyFiZc2VrJNyWJKf/g1c/MAmwgjRrXsysYEpSUpQOcRdyP546X41HgdQsP7zlc/rlHyzGf1uLCssLWPn8rc7+NkiNnKzt6JvJUApRP2xr/g4el/hpoJbBf9+eq14cGJ2JWXm6oAcwwNM7UZuRego6hLfk8+W6gDnxBSZZpfieJCd+r6gHrQAAAYHUlEQVR42u2de1xTV7bHMyBggURaZSxoVVT6sDqiTsdqrbQztkUdsQ+pVdrS1sKo9XrnYecEkCQk5CRBSyEhCQQIECA8FAHBkQpSwQeoRYGUIULVaq223lrqHcfrtcLnrnVOgDzOCSrMZ1Dv+qPtxyY5+3z3b6291tr7HDkl96dJ//F3K/tv8k6+y7lPifwP2qeffgL2w/H/0omHi4ksPqM1uTCtum7r1q3V1WmFJ/ZmxMvuASLfIZFP+5icOlQs0EmHhUl8+tE6c1JurkSSACaR5OQkxcTEdNQdO5EhG+lI/v7NN198sZ1mcvzQ/yZq70gmLEzi0wvzknITjLGxKSlx+XH5+XGalFhjgiQnqR7AbC3cGz+SoYh1KoFA8NV2ZHL80D+L1XeGhJFJfPLWmKSE2FiNonZfZsGOHeU7mgoya+RyRVyKUZKTnVRfn20+lkGOWCakWAT21fZPPoVY8ref+PqSoTKJT46OyTXG5strCnZ9yU8UCFRogovXyjNr5Yr8tgRJdlJ2do6kZ690JIuF3L4dZPLzgb+dSRQOkYmsdWseaCROk7lrZ6JArROKxJSJhHqt6uLBfYRcoTFBcJEkGDW9l6UjmcknyOT4oTMC0dCYtKRFx0hAI6Xb+AK1XiwlbSQp1O05WEM0K9pMgEShIGqPiUasB5GfDhMTEElMQqy8srxYoBVJmTxVv6eJAK3ExSmaCYNSWfojeX8zkR0FvzGmyPd9yVcLpWzxS3epkiBOnzYYqiqKinaoxCOYySdDZhJfCEhi84n2nQJneR8pPFJqIJRKIJJ6i6++r5nI0hBJHNFeLNA7dwjxnkwgkpqaup+vEpH3MRNZ4dZoCxLhYPcp1RYAksb9I1cl1LrzySfbh8QEYkl0jDGO6Nw5OBKA8n1RauOukYyEZjI0nSRvjc5L0BCV3YM5DmXpFUXXt41oJMPAJB2Q5MYSRDlfdxtIZKUV57bdaWX1b2Lyt7tlEl+NwUROdN5evZSRfOSGYGQjGTqTo7TnVO0S3FZtQIq0WuGIrnaoegdj7IG7ZZIRjZ4DMuFrb+9OSSlZUnJ/M0mLjo5JiCOq9t/x1+9bJunRHZRMzu1US/+fCc2kMA8qP4gmNxP1wzemsoasrM+6uj7Laii7vS9c/fzs1xfOnzx5/sLXZz8fum/STE45YVLW8Nm3uw8f3n0lq8yBSUt0Xh4uOhXbhq2gK7vywctBM8CCgoKenrXq24bBbvHqlgubN/bZZrALWwaTrKwlvbU1OfmoxQrR0tJWrqw+0dLHZDs7k7IsaoRBtK3qKrNlkpyXZ5ag69zQDk/kzPrg2RmB06f7gQUGznjyyaAnA1Z1ObvFq38+CUQiI997773IyA0bLGTOip0Mp6U1ra7DnJfXEQ3WkWeOScqRGDUKhYLovRxP9jH5gYVJ2ZWXZ+AQwWCAQUFPPvn0FakVE1l1HnYICOXY4XGdrFVBM6b7jZ84e9682XMCfPz8Jz8JNmFOFtsdXj0LRCIj33z9pWI+/92333jLgmXDyc9ZQMpaq5NwQ0GSmxsTA1wASW6CMQWAEKXLBFqRhcl2NiafgUSmT5/4GIxw4ni/QGqAk+f0i5lTkgHRJKlNQVRNG45Vp+zwQiAyZd4SfiI2cgWrJ/lRVCZMnrCGed4/Po9IXnmJL1Br9Xq9Ti14JzKKhrLhI6avyFqjcxNi27KfeCKnLdYoyY6JQSQ1vr6Vlef2F1uQAJMfWJiUgYynT59Ej1Dw/hw/fxTzZP/JfVrmlCTHxMTgqlNVPgzhJGspXG/87OWJKq2QauPq1aun+PhPnjBhwuQxc5hKqbMnT26MfOsFuBchFVhJqUi76T2KyoYNUX9wLEhbVsJwfZu6+YmJideaNG1tIBfwm4LiG2CJ/c0wmslxRyYNOMQpc/GCOEKhdvUUnLTJ/j5TLFA4JdUxMUkYTqp2DX0lvvIyqGT8XL5K3z/BUqFqoo+PP0AZ4xPgGGtpJC/x1VY3T4o2vRcRtQEsap0DlNatMZLYzC/5Kp1eKNRrj+yLy481ouMUqHV6/UB2jUx+YNBJlmWI6r7ODylcDxqZPHmMj89EetI4smhgkpACTLqHHGKv2F+PbkGpA3x8xkwGJj4B9hUmINkMKuHbFU/iTeERUVEboqLWRbxjC6UVM+7MYoGOhk6K9pTKFfkpKfkKosfmk8AE7NQhOyYWJDYFrHg9uLe/jw+PN5v6CU5LUlJSrlFDEFXLdENk8hl1vccdegjSLk+ezxgwHy8799mCsSR8gWPXQfzHcFQKMIn4SGSjko6kWNOXVg0N8WWTHKgo5IThoPUnSUTyw/FD/7RhUrb05Wenj59qV8OI5/gDEq6Ht7sAB8JJp5jEAZNruiHGkpfxehOXO4Yl8RqeD0Lx4XF/Zz2ZEF5PbnxrUTFDIBO9iUpBJuGbBv5vxlYsQppsGhrSEwQygTWn9ojV75BfMTE5jNPm7TDELh9A4u3u7jobYXNac3NzJbHwi5XXhrYUl63C63FnMvXpxLO4FBMvD8/1A8O5egE9J3RBIkPsJT8Pj1hHMQl7s9+nZdXRkF1qum1vSVynUORTUAqsWDEygWkLApkk2ntEw3ieh6e7q6vraPxpztE+JlVDZLKbksm45UyRmuzieoFSfHgeHpMGxgPB5OTG8NCXGNc76TsRCAWYrHhb1B9MUCY1drkledkXIgpAMVRZCYWJiWXa5jpcsGw8F5CMdnEZvVoITAqHiQlMwcIZftzHmBM/6Rxg4gM68fBc3TfEq+cpmSziM8d2FMo61MmKVyzeT8tEXmp/CWkPMGmDiELsGABOMfnZlgkEPGraHC64ChzH1cXF5aG52EDipEkgIUQmxLIhxRPw1KDA8d4zBcxJznoehBTUieekvhHhmrMxMvRFlvRZ+ocICkpYSMi79F215uVh/Z7pkFvuVeS3teXLDUTpgAKYmKxaiIvAOLuDBmXfBvEQyahHl/Op0ztWTBYPZS1uWAjX8+N5z2VJcsoCUCg8Lrjt+/S4SZQJuM6LbOnzWQuTFSFv0CNLw/o9hch0wC6rB53kg04qL4oGmPxszwTG+CxIeaLNQYOsVbAMe7iPfmguP1FFr/CctIQEYJIPTMqHkrN9u3BhEFzPcwkb2Ne8MJ5wPdzc59EC/xiRbAgPWcCWPosjKSYrQoIXUR+hMilYIR2ZkCtBJ+A7VVb+z8DkCjKZzptkHXSXAhGe9+jHQSKQ19Jj5xTi0SwKcoFqCEyWPku5jvtytiSni+c1ZgzPC5g8TF8HamF0HXYm5B8svhMc/C7OLJVJteUT+xyF1ZoCTBSEsmLA/x2ZQJ3zbFCg3wCTsisLAyEv8Xxs7vI+idBMko3AxIhMSodQ7zQEBUGpSTFhW6oDIG+jmLiuFlMRdvMgTEr+vM7CZP7rSDo9F5iAomsuOjBpMQITgqgoWtYvU0cmDS/jGP15E+k/aPggCIjwxtlIhGbSajRiuWDrjHdsXXC5GX7IhG3xIucAEy9g4uo6D2f9rygTYBLMzuTzfiYL8FZbJbhCxslrHRdIWXZbiuI0UZHa7YRJ1rPIxIdmkrU00N/PhztpbrGNRGgmGbFtQCWFCrJ3vxjvnjFjRqA/MFnCunitgaWYZjIVr/Pxxs0YTkKDX2RlIo3sY/IihrpWKvJp5MRiR//swDtQFjXu1Dlhgp2/6X68cQL97imYGYybihLRO/QjOPEShJKCq3vB3S88HyAT1MnzrEVTl9cYZALZ4mP4mS1UhyQ8NISdCbmZZjJ//q/xM+kwd8Y2YFLguBjUGaEIrCjq5DuJsZ9hM9TPjztu3pyAWXNmz56JUYTp5BGH7E2JbWsDSRLEvj13HVBWBc4IRCaez7FybRgDUHiYQT+stWayiL2Vdd6GCTV74CPymiMO46xrA9cpSp02sMwyMwkEf/F+Xq1V4dFFBolY+ifH8lNiY2MxNSYu3ZXz4BHipZMDaSZTWRf0soAxwASTIysmEcCE/Vzi1/RabGFC9sai5cvljk6+tQ1lktptnbM5MAnEMQKTeWqhUCQSi6Wsexl78yHhabM4z2CrcfrKarCVlFX39NT19j5R2gpfWgqX8/cb7+H9GPviFYC+AzpxecSKSVhoyLusM3GWYhI8/ynav45q2mD64uLkpfbgZWZYJIpSx1qVCQzxJHA6DBKYTBokEeOUxJugqkxJwZZ37RHRIERy0LLrzebeXnN9do3GYFB+r4YvrfL3RyZc74nsnjALmHDdoKx4HEf+OfbRNkQCk9dZ3Q2ZrEUm9NrUYsqHkWriFPJLdtJqSUCZNHZbXZz86pQ9kxl+/v7AxMNzkMYzp4TswVI7BbsyRJOztlJGta9GI5fLNb4mpGLONtUalMpyqiF0GK6Ga5un52pWT5hDL8UuLjN11LpDMcEgyzptWygm85966gXqI+RKuUKuiFNARNlj+5XkNpTJrUSbXoE9k4ankQlO3HP6wfYB94JEqAaE4rTvEVbltxSaNDU1+/aVZmYWNDWBVupzTAZlRXsxdaTtip8fMuF5ez/HinUpMnEf7TJqCQ7p6ubIqA1RkVSQZbvolihgEgJMLJXsjzVyNBjpEzZXiTfng0ym2bTrHJmUraIHyfUYxHmAibSegoL/sOnK2DHJ2LPn4o1EMIFA8KEpJxs9R1l0iz6d0eCPO1xQ93o/xno9ZOINMnmEHuSFyMioqEinAQWZhIHr/NqyxJIf1kIaRSAW6+arrNqoIIqmweyUOGNS8i0MESeO67FaNNh+cTKFHpxHTsg/ZP20VKQHE1Ihe2+tqabGF5AU7adjKvk05EB4Oe++spfRd6hwYmnpbImIiIyMjAgPDX2DLaCcjYIQCzJZ0Hdb4kvIxEDAeHv7Tyu3VEsURNUtuzOYyOTnU7Z18XgYox9W55OcZmIcSpKnmxUW27eHVVZWP5Mur/X1JfBA6H6LLF7zoQyEwuqsEGM93F1cRlkcQfpeREQE9oxCQ9nWqq+jaNf5bb/2RJcopYBW8nNOIBVZS3J0roao3Ga3WYBMfrZjghPnB0XfGB7XqVCQCXkML4JEQJU9t3XGj9Bo0HNS+5lkcWkm7M5aFgArMcjkUUsPifwoPByoRISHhb7OgvF81LoVwU+h6/Rn7KIjmRUVVTBeRazEXJ2WVh1tTjIqKrsdTtcxMCnZPYZSsw+PN85ZRKHO5IhKDQYaCmC5dBuVYLq8j8kuNdlX4vFoJmzOmjWBWnVG9TfN//oWDSUs7E3mEZIb10WgTGwatmLtsvbKKqASl5Bk7ojuMCeZFLXbEh0yq34mPw0waeDyLHLmzXEy9RQTci/4aB+U2g8Hz/AzNBpfC5M+z+zicrk8MBAKs7PuBia0TPo24D4KCwunhBL2NuMC/nGfTGwCv1Sovri4qb20tLSg15xnjpHkEzcZzpwxMSFf4/F4FihrRM6ZlIgPEgNKMQ3+sFIGhBM7JtLZHh6IhcsW1WfRC7HV3orozVCgAhb2FqNQLlDR5BmH3RipSKdWCWAF7K2PicmBNYfp4AyT75Q0eHL7pbJe7JxJyY/gPQbCEmlNgz6rlOHr61try6REP86DosLlTWS6Q3AdiCaj5lpt5pB/Cl1hofIOg5RRJug5DNs/pFQsEgr3JkiSciRQKC9jUCYyOWXPhFyDY7RQWSN2zoS8XINrHEFDqRlMKRkmkwMTcr2ntzdNZTbDHaJMXEY9aqNy8R9DQkKACmD5o6O2Tq5bC7nJb9jPYp4wJkgkpji5oZyZySlkYrtfLJ4EY+zTymtMZXHZwNly6YeVSqUStEJB0ZwQ3wYTWIo5A0xKxGvc3Dw9KbE4Outh7Jy4PGK3DSp6B6CErEAom8QOnUf0nAVOTrCfaDOaEoxxCqKGIYGwMDlge7acbBjnCWPkeVFUZjmcE2o4DH/U/1yG+MPKCoTSDA4kj9N87/QBrgyLTDjWTEpEv3N3d3OjtGKvyyteXm4UErskQvhGcDAFJSL8T2ImJLbJqd22TpvR6GvUQKH2hONoKSbHjwMUm14E2eVOzRzXCzcmJyy1oZI1i7teJLV6fgeh0FQAikaT7cx/MkwWJDZMSOFzrkCF8qDXyqwvdpiLSB4tVtnvJZP6V4NpKhERF6x4/fU8Ipn/G6cPCMXnUI03TCCyHULgdz9TRA4cOP57G08Wr4cxuuPMeeFOwoRZh7saysCyriyd4uGxHs/BWD3nJT5yrqiPCkDx7WF/hDgDkFSk2jMBKKtHu7q6u4EDcQMGTvVlzcLMZNRcvspxe50Ublo0f35wyIoVayMi/3yV/v8ffx0VAUh+/dtEtbNzfuTKNg1Vu4L52nv7P746APH1p5/O/PPAN//4j//+y3ffWcYjVuEYYZAQWAALcgkICJgA9amH+xJ6H9Aa4Z6CoiLEQlPxrenZy/IYfoYB83qOPRNIM1VTXcGQilcAzEBDQ9fhWVQX9pHlzDdIitSvPkNRCQMqm89/feE8pGprVwQ/80KxYJB3L/xoQo1YqpLvbYD/5asvzvz0SzCgcgjU8sU3/9nnhGI1NUbEgpMHXHjAw83NbfQSOvWzeW5UqlvciFTouAJUfHtPtDhiiT9Rb1HJL36xyy7ki3XvT7XMA/osF9vSIJKHl/BVehZnlOpVr1JaCVmxdi3kcGvXhq0IeeWF4kT1YE9XkXs1loowLk6hsA4q0m++OPPLATtz5leJatHABVePchk92pUi40aZu6ury8y+dz1w7JS8p6kxtR8LelBN77ET/a+zkMla0pN7TNQqDEiud968Zr8MkiLt+4+PcqGweEOM93Zzf5jaVmL3AlKsU727YNEzzwTjKhQSuuiVV3/LF6idPfmBB4aPrqzrrcUEwnAaVkoIK9mX+y8h/f3vf2VjxdZTAtpc8rALZTQZV5eHZoKOLbGL4zC8IzcbU1NTLVhoLr415t66Hmy/1lMLDvoN8Ni1k5/IEAOlIq3q/ecfn/ow2NSpj89djs+zi51OOSnWaze9/eqLlL3+9vsqNeMmg4VHenK1OScBN0OJKiVUhEoKCiilZiDSSoU6G7Nr0UOBIHj+0Ycs9sjM5dZzwHH0b+3F8k4LFpoLbQT9LyW4zbn2W9t28gUwciHjveIT61oVvlxCAB/S6kW3cXyexMf/dVownV4oZv2CLL2wIyfBCJH1tKGy8ty5zs7KIgyAdEwpvf23BUhFetzRoJtkKhyjfR5rS0WnulY+9noqxQXJABo0+I/Kc2Nv7u++kYi/4mTklvRbRO0Y3MFGGonmbNuktTomxxeAVGY2lXdfu3ERbuhGO0AhqLqEMDxxJ+cU8f0XQmySiW1nlsP8YaFWdXHZ/mntYzuvX29sbLx+rnNs+81bu7p34uFjtU4vEv87HmpKr85LSshXEJn7KZWiosC0iytppTQ3GwwHhUMfGIedoV6rtogr0aIw9AOg+m96yEuWHG3Ohip4H75fQjegUnwwHnwcpALuXblH/C9jMlB9CvV0H/ZO/WDYkRRG5yUBkps7Ey3H0AfmT12gJOiIpzyoJ/+VTEaWFUZ31PvKiWnFDImOVNdErwZKZefQn3q+Z5gkR3eYJQpDezFjBUTqD9JMKiqPiB4UJhkdHXk5+YbKLwXMRSEp7EHngdRpmf5BYZKWl1efICfaWZ+TJ3U1qJOiosW6B4RJS4zZnKMhlPtZ91FLyEsUk9RdQ3685B5hklxfnwTRpKLbyb5MS60BW3/bHhQm1Tk5OSaFoWqZkxsmsykm13QPCJNeiUQCuYnS6TNGvdjoun7jQYmxZpPJpAEm+7XOmRSl3rzjV9TdszrRtLUBE0O7k3giy0Emw/Dg+D3CpIdqBRAGZ6fL0uWGCpsjbfc5kxPUERmAwn5oqGQlyKRx2zA8JH2PMIk3GaDsBWtmbQaka4iK1FvDIJN7hQl5jMCyt5lobmZ5x2RLPcikvXg4XkNxr+T2olIltgMMzfLmOqYtyhYzILm9F6ndN0zIy+ew/UngzpPpmD0VWTLuJYzdKdAPR4PnnukVSC/voxrDEFfkGlNdckbf659lLelp2XKDsvJW8fAguYd6SpZdSqDS3Cz39TVl9/bgCfc6s0mDPYKxXzJtvd7nTEqkumWd/Xu3uO+EJm+mOkljtzndVbtvmZSQQvWy9kabfSfcYak6d7Ob3/fakweNCe70qi8untZ5ndq/LSpKbbze2V7efSNRpRUN4xvD7rW/G0Iq0quPLC7fcfNme/vNph2Ll11k3Y18YJggFrFIT++ianV6/b9gu+le/TtESHKwfdS7t/8Dw4+o6YNxgfwAAAAASUVORK5CYII=);
}
+1 if you like this :)

Pop up to save image in asp.net

I am using asp.net 3.5 and C#.
I have a image which I want user can download.
Like, there would be a download button or link. When user click on this link he will be prompted with a pop up to save that image to his desktop.
I have tried with
<a href ="path" > </a>
but it is opening the image in other page, I want user to be prompted to either save or view the image,
please help
Thanks in advance
You need to write an IHttpHandler that serves the image along with a Content-Disposition header.
For example:
Response.AppendHeader("Content-Disposition", "attachment; filename=\"MyImage.png\"");
Response.TransmitFile(path);
You would probably pass the image name on the query-string.
If so, make sure it doesn't contain / or \, or attackers will be able to read arbitrary files.
You need to have another page or, better yet, an HttpHandler, that takes the image path as part of the query string or as a post parameter that will send the response with Content-Disposition set to attachment. Setting the content disposition this way will cause the browser to display the file download dialog. A slightly easier way, though it depends on the user doing something extra is simply to have the link open the image in a new page and let the user right-click on it and do a "Save As".
Download
or
<a href="/path/to/image" target="_blank">
Load Image in New Window then Use Save As</a>

Is there a way to get images to display with ASP.NET and app_offline.htm?

When using the app_offline.htm feature of ASP.NET, it only allows html, but no images. Is there a way to get images to display without having to point them to a different url on another site?
Yes, it just can't come from the site that has the app_offline.htm file. The image would have to be hosted elsewhere.
Another solution is to embed the image inside the app_offline.htm page using a data URI. There is wide support for this these days - see the following for full details -
http://en.wikipedia.org/wiki/Data_URI_scheme
If you don't support browsers prior to IE 8, you can always embed the images using a data URI.
http://css-tricks.com/data-uris/
If you're willing to do a little more work you can easily create a custom page to take the application offline.
One possible solution:
Create DisplayOfflineMessage.aspx: Contains label to display your offline message from Application["OfflineMessage"].
ManageOfflineStatus.aspx: Contains an offline/online checkbox, textarea for offline message and an update button. The update button sets two application level variables, one for the message and a flag that states if the application is online. (This page should only be accessible to admins)
Then in Global.asax
public void Application_Start(object sender, EventArgs e)
{
Application["OfflineMessage"] = "This website is offline.";
Application["IsOffline"] = false;
}
public void Application_OnBeginRequest(object sender, EventArgs e)
{
bool offline = Convert.ToBoolean(Application["IsOffline"]);
if (offline)
{
// TODO: allow access to DisplayOfflineMessage.aspx and ManageOfflineStatus.aspx
// redirct requests to all other pages
Response.Redirect("~/DisplayOfflineMessage.aspx");
}
}
I have an idea.
You can create separate application, pointed to the same folder, without ASP.NET enabled. Then accessing to images by this application will not be affected by app_offline.htm file.
Or, point that application direсtly to folder with static content, there will not be any app_offline files.
But, of course, you need to assign separate dns name for this application, kind of static.somedomain.com.
You could just convert your images to base64 and then display them:
<html>
<body>
<h1>
Web under maintenance with image in base64
</h1>
<img src="data:image/png;base64,iVBORw0K...=">
</body>
</html>
I've created a Fiddle where you can see it in action

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