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How to run JavaScript on a UIWebView with stringByEvaluatingJavaScript(from:)

Swift version: 5.1

Paul Hudson    @twostraws   

If you’re still using the deprecated UIWebView, you can run custom JavaScript on it using the method stringByEvaluatingJavaScript(from:). The method returns an optional string, which means if the code returns a value you'll get it back otherwise you'll get back nil.

Here's an example that pulls out the current page's title:

let pageTitle = yourUIWebView.stringByEvaluatingJavaScript(from: "document.title")

Note: if you're using a WKWebView you can use its title property directly to get the same thing.

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Available from iOS 2.0

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