Im trying to implement dynamic images on my site. Basically, there is a list box, and when the user selects an option, it calls a service that streams back a base64 encoded image that will be the preview of what they're looking at.in FF you can do this: img.src = "data:image/png;base64," + args ; This doesnt work for IE. from what ive learned, IE doesnt support this type of inline coding.
I was thinking that maybe the next best solution would be to convert the base64 back into binary, and set the new image object to that source. something like this:
Code:
var img = new image();
img.source = binarydata;
now obviously, img.source isnt a real method. but i would like to be ale to set the binary data as the image.
possiblities: Is there anyway to save that binary as a file on the client? and then be able to reference that file as the picture img.src = "images/" + newfilename;
Some other alternatives is to stream back a reference on the server to get the picture, this would require two callbacks, which i dont want.
Also, there is a method of turning the image into a big array of HTMl elements, and each element holds a color, being a pixel. im not doing that, that is the biggest hack job i have ever seen.
I've search far and wide for an answer, so forgive me if this is a stupid question. (Well, it probably is.)
Consider the following javascript:
var foo = new Image(); foo.src = "http://some.server.com/some_filename.gif";
Now, the browser will retrieve 'some_filename.gif' from some.server.com and put it into the object foo. What I want to do is then subsequently analyze the actual binary data contained inside some_filename.gif. (Specifically, I just need to look at the first few bytes.) Is there any way to do this in just JavaScript?
I'm trying to get the binary data of an image object.
I've found articles to writing binary to be the source of an image, but they don't tell you how to do the reverse. Pretty much, after the page loads I want to do something like.
For those that are curious why I'm doing this its for another project I'm working on where I store the binary data somewhere else after load, but for technical reasons this has to be done client side for if I do it server side I'm not getting the results I need for this project.
According to my previous post with popups hanging, now I'm trying to bypass this strange behaviour using loading JavaScript image not by image.src=URL but straight away from stream using HTTP GET method.
The problem is, how to assign stream from downloaded image (ex. GIF89a) to a JavaScript Image object ? Code:
I am using javascript as the scripting language in an asp page. I would like to write the binary image into the web page using javascript. I am able to do this using vbscript as below,<%@ Language=VBScript %>
I'm reading the content of a local binary file with the method mentioned here: [URL]
Then I'm getting the data as a string where each character represents the binary value. I have successfully sent that string with Mozilla's XmlHttpRequest's sendAsBinary method, but IE 7's version doesn't have that method...
Using the send method almost works, the only problem is that binary content can be represented as the asciicode 0. This means that the string read by sent is cut off as soon as it is encountered. That means that the part before the first NULL character (asciicode = 0) is successfully sent to the server.
The solution I have made right now is to increment each character's asciicode on the client side by one and decrement them on the server before converting the character to the binary representation. The downside with this is that the size of the data sent between the client and server gets larger than the original filesize. Ex: 8kb file grows to ~12kb.
I am creating a form using html5 and javascript. Am using <input type = file> tag to browse and display the image file. I need to convert the image file to binary file to store it in web database.
Is there any method to convert image file to binary file.
I am creating a form using html5 and javascript. I need to display user image and am using <input type=file> tag to browse the image file. Now I need to convert the image file to binary file to store it in the web database.
Is there any method in javascript for binary conversion.. convert image file to binary file.
Is there any way at all to create a new template object that inherits from the built in Date object so as to be able to add new methods to that child object without adding them to the built in Date object? I've tried everything I can think of and as far as I can tell it keeps referencing the Date function instead of the Date object and so doesn't work.
I have an object with a single Method to load content from a xml file. The problem is... how do I add a property to the object to store the data loaded?? I tryed adding a simple Array inside the object, but didn't work.
I have created a servlet that does nothing more than create a XML file.i have got some JQuery code that reloads the servlet to get the XML data.This works fine and i am able to load the data i want, the problem i have is that when the data is loaded to the jsp page it displays [object Document] in front of my output.
php page is echoing out:{"species":"Please select a species!"} I double checked the response from the php and firebug shows the same. On success alert is not alerting the JSON data instead, I'm receiving [object Object]. Why is that and how do what should I do to fix this?
I know I can use the functions like parseFromString() to access and modify an existing XML documents, but is it possible to use JavaScript to create a blank xml document?
I want to take data entered into the client, package it up as XML and use ajax to transmit it to the server. So far I've written my own class to create a simple xml document, but I'd like to do it properly with the inbuilt functions.
I am looking for the best performing solution for modifying and iterating an object graph in JavaScript. I have outlined below a simplified example of the object model and examples of how I will be using this graph.
Object model:
Two objects, [BadApples] and [GoodApples] each contains a collection of [Apple] items (500 max). [Apple] simply has an ID and a name.
Requirements:
A quick way of determining whether a certain apple exists in either [GoodApples] or [BadApples] (by ID).
A quick way of iterating through [GoodApples] and [BadApples] in order to update the web page.
A way of moving a certain [Apple] (by ID) between [GoodApples] and [BadApples].
I currently have this implemented using arrays, but iterating these arrays is expensive. Is there an implementation of a binary-tree for JavaScript? The real-world application may contain many hundreds of nodes, and performance is crucial.
I am trying to convert binary to decimal with this function but it doesn't convert to decimal, but does decimal to binary. Code: function bin2dec() { var x = document.getElementById("bin").value; if ((/[^0-1]/g.test(x)) || x == "") { alert ("You must enter an integer binary number!"); document.getElementById("bin").value = ""; document.getElementById("bin").focus(); return false; } x = parseInt(x); var dec = x.toString(10); var hex = x.toString(16).toUpperCase(); var octal = x.toString(8); var figs = "The decimal representation of " + x + " is " + dec + "<br>"; figs = figs + "The hexadecimal representation of " + x + " is " + hex + "<br>"; figs = figs + "The octal representation of " + x + " is " + octal + "<br>"; document.getElementById("result").innerHTML = figs; }
Can anyone suggest how to create an arbitrary object at runtime WITHOUT using the deprecated eval() function. The eval() method works ok (see below), but is not ideal.
function Client() { } Client.prototype.fullname = "John Smith"; var s = "Client"; eval("var o = new " + s + "();"); alert(o.fullname);
Note: I want the type name of the object to be represented as a string (in this case "Client" -- this is a non-negotiable requirement).
I also tried the following (which appears to fail):
function Client() { } Client.prototype.fullname = "John Smith"; var s = "Client"; var o = new Object(); o.construct = s; alert(o.fullname);
eval() is handy but not future-proof, so any suggestions would be welcome.
I am trying to create an xmlhttprequest object to update the shopping cart on my web page without submitting the entire page to the server for processing. However, what I have done so far is not working. All that is happening when I click the "update cart" button is the page sort of flashes and the check marks in the remove item check boxes disappear. The first code snippet is the "traditional" way of submitting the whole page to the server for processing - and it works. The second snippet is what I have done to try and implement AJAX to submit only the shopping cart - and it does not work.
