Stringifying postMessage data vs leaving as Object

Hello!

Feature request incoming:

I noticed that when calling window.ReactNative.postMessage(data) from web, the param (data) passed in must be a string (which is consistent with the docs for this project).

I was wondering what the reason is for stringify-ing/enforcing that a string is passed?

Why not allow web to send Objects, arrays, strings, numbers etc?

I dug in and modified the source code here: https://github.com/react-native-community/react-native-webview/blob/master/ios/RNCWebView.m#L161

By removing String(data) in favor of just `data, I confirmed that we can send objects over the bridge.

For example

Web:

window.ReactNative.postMessage({value: 'Hello, world!', amount: 100});

Native:

<WebView ... onMessage={(event) => {
        const object = event.nativeEvent.data // {value: 'Hello, world!', amount: 100}
	    object.value //'Hello, world!'
        object.amount // 100
    }
}/>

Any reason for explicitly forcing strings?

And would we be interested in a PR to change this behavior 😄 ?

[chirag04]

postMessage as per mdn link below supports a broad variety of data objects for the message argument. It would be nice to not enforce string only for postMessage because it will break with a third-part site in webview integration.

https://developer.mozilla.org/en-US/docs/Web/API/Window/postMessage

Data to be sent to the other window. The data is serialized using the structured clone algorithm. This means you can pass a broad variety of data objects safely to the destination window without having to serialize them yourself. [1]

[weraaaaz]

Can we reopen this? It causes problems with third-party sites 😦