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Pass variable from Swift to javascript function


Having trouble using JSContext to pass a variable to a javascript function. The error says stringToSend is undefined:

func sendSomething(stringToSend : String) {
        appController?.evaluateInJavaScriptContext({ (context) -> Void in
            context.evaluateScript("myJSFunction(stringToSend)")
            }, completion: { (evaluated) -> Void in
                print("we have completed: \(evaluated)")
        })
    }

Solution

  • Here is how I like to communicate from Swift to Javascript:

    func sendSomething(stringToSend : String) {
        appController?.evaluateInJavaScriptContext({ (context) -> Void in
    
           //Get a reference to the "myJSFunction" method that you've implemented in JavaScript
           let myJSFunction = evaluation.objectForKeyedSubscript("myJSFunction")
    
           //Call your JavaScript method with an array of arguments
           myJSFunction.callWithArguments([stringToSend])
    
           }, completion: { (evaluated) -> Void in
              print("we have completed: \(evaluated)")
        })
    }
    

    Make sure myJSFunction is implemented in your javascript context when you call this method.

    Your stringToSend String will automatically be mapped to a javascript string when using callWithArguments.