Is it possible for a view to display a WebImage without saving it to a file first?

Question

I'm not really sure if I'm using the WebImage class correctly.

I have a controller that pulls a photo and some related information (comments, upload date, file name) from the database. I want to return a partial view that contains this information, and display the image along with the extra info.

So I created a new WebImage from the byte array, but how do I display it?

According to this article it should be pretty simple

1. You need to work with Razor syntax and create a variable that will contain the image:
   @{ var myImage = WebImage("/Content/myImage.jpg") // Work with the image… }

2. Then, in order to load the image in the page, you have to show the variable that contains the image inside an HTML <img/> tag:
   <img src="@myImage"/>

Except that doesn't work, it just outputs <img src="System.Web.Helpers.WebImage"> and calling .Write doesn't help.

Is there any way to do this or do I need to split up my action into two different actions, one to return the photo information and one to return the photo itself?

Answer 1

You can write it out on the fly!

You just don't use WebImage.Save() like you'd think, instead you use WebImage.GetBytes().

In this example, you've already saved an image as a byte array to the database. Simplified it a bit to only handle jpegs.

    /// <summary>
    /// Reference this in HTML as <img src="/Photo/WatermarkedImage/{ID}" />
    /// Simplistic example supporting only jpeg images.
    /// </summary>
    /// <param name="ID">Photo ID</param>
    public ActionResult WatermarkedImage(Guid ID)
    {
        // Attempt to fetch the photo record from the database using Entity Framework 4.2.
        var photo = db.Photos.Find(ID);

        if (photo != null) // Found the indicated photo record.
        {
            // Create WebImage from photo data.
            // Should have 'using System.Web.Helpers' but just to make it clear...
            var wi = new System.Web.Helpers.WebImage(photo.Data); 

            // Apply the watermark.
            wi.AddImageWatermark(Server.MapPath("~/Content/Images/Watermark.png"), 
                                 opacity: 75, 
                                 horizontalAlign: "Center", 
                                 verticalAlign: "Bottom");

            // Extract byte array.
            var image = wi.GetBytes("image/jpeg");

            // Return byte array as jpeg.
            return File(image, "image/jpeg");
        }
        else // Did not find a record with passed ID.
        {
            return null; // 'Missing image' icon will display on browser.
        }
    }

Answer 2

There isn't anyway to do it in a single razor view... you need to create a seperate action to render the image.

The img tag on the page is going to make a SEPERATE http call to the server based on the url provided in the img src.