ipad web app加载本地图像

Question

Can a web app load an image from it's local store onto the webpage?

Thanks

Answer 1

What do you mean by "local store"?

If you mean the HTML5 applicationCache, then yes, any images that are in the applicationCache are available for use online or offline.

If you mean from the Web SQL database or the localStorage API, then yes, but the images must be base64-encoded as text and then loaded as data URLs.

If you mean the photos in the user's personal collection on a mobile device or computer, then no, that's not possible.

Answer 2

Use a manifest file. Google it.

It's 2 lines of code and you need to declare it in your .htaccess file

Answer 3

I should think not, as it can open vulnerable security risk:

• If a web app can load an image from local storage, it means that there's a facility to browse local storage device (either via the browser JS engine or the web app). The malicious attacker can use this to gain valuable user information.
• If the image could be loaded, what will be the path of the image? And if this path is valid, can every user viewing your web application open the image?

iPad doesn't have a storage directory like a PC (ie directory structure, eg home/user/* structure). Each application can store data that is only visible to the application (unless the application can allow sharing).

It's better to store image on server machine and load images from there.