I have a .NET web service that takes a byte array.
I have a GWT client where I want the user to select a file using the FileUpload control and send it to the web service via HTTP stream.
The file upload control contains a method to get the file path of the selected file. How can I then get that file and convert it to a byte array?
I'm open to suggestions on how to get the file to my web service, not quite sure the Byte array will work...
If you want to convert the file in GWT, meaning in the browser. It's not possible to do in the browser using only JavaScript. FileUpload is a html input type file upload can only send the file to a server as in submit a form. For security reasons browsers can't read files from your file system. (You could use a plugin like a flash plugin to get it to work, although I have no examples at hand).
If you want to send the file content to your webservice, you need to or upload it directly to the webservice or send it to another server, convert it and from that server submit it to your webservice or write or find some (flash) plugin that does it for you.
This link maybe helpful yo you How to convert a byte array to a string, and string to a byte array with GWT
The String(byte[] bytes) constructor and String.getBytes() method are not implemented by GWT JRE emulation String class.
This is not possible purely in Javascript(yet) but could be done with flash or a signed applet. Personally what I would do is create a signed applet that would be somewhere on the page but not visible. When the user selects a file to send to the server you would get the file location from the input and send it to the applet which will load the file and return the data to Javascript as a byte array. If you are flexable with changing the web service to accept multi-part form data then you can do so and just include the file upload field as part of a form and submit the form. Now what you want to do is possible with HTML5 and a demonstration can be seen here, so if you are capable of specifying that the users be using at least a semi-HTML5 compliant browser such as FF3.6 or Chrome 6 you may be in luck.
