问题
I am working on a Mac app that uses a JSContext for some functionality.
It uses a call like this (where ctx
is a JSContext
):
let result: JSValue? = ctx.evaluateScript("someFunction")?.call(withArguments: [someArg1!, someArg2])
Inside the someFunction
script, we need to parse a directory and determine whether it exists on the filesystem. Apple's JavaScriptCore API does not have filesystem access as far as I can tell.
Is there some way I can have a function like this in swift:
public static func isAppDirectory(_ path: String) -> Bool {
var isDirectory = ObjCBool(true)
let exists = FileManager.default.fileExists(atPath: path, isDirectory: &isDirectory)
return exists && isDirectory.boolValue
}
and pass some custom function pointer into the JSContext to call that function?
回答1:
You could set up a message handler for a WKWebView
. You can then pass data between web view and your app. Answer in Objective-C, but easily adaptable. (I think you should be able to set the message handlers in JavaScriptCore too, but I'm not familiar with it.)
// Set this while configuring WKWebView.
// For this example, we'll use self as the message handler,
// meaning the class that originally sets up the view
[webView.configuration.userContentController addScriptMessageHandler:self name:@"testPath"];
You can now send a string to the app from JavaScript:
function testPath(path) {
window.webkit.messageHandlers.testPath.postMessage(path);
}
The message handler in Objective-C:
- (void)userContentController:(WKUserContentController *)userContentController didReceiveScriptMessage:(WKScriptMessage *) message{
// .name is the handler's name,
// .body is the message itself, in this case the path
if ([message.name isEqualToString:@"testPath"]) {
...
[webView evaluateJavaScript:@"doSomething()"];
}
}
Note that the webkit messages are asynchronous, so you need to implement some sort of structure to continue running your JS code later.
Hope this helps.
来源:https://stackoverflow.com/questions/61315468/access-to-filesystem-in-a-mac-app-jscontext