syscall/js
syscall/js
js.ValueGetSetIndexSetIndexInvokeCall
js.Valuejs.Undefinedjs.Nulljs.Global
Hello, WebAssembly!
<!doctype html>
<!--
Copyright 2018 The Go Authors. All rights reserved.
Use of this source code is governed by a BSD-style
license that can be found in the LICENSE file.
-->
<html>

<head>
    <meta charset="utf-8">
    <title>Go wasm</title>
</head>

<body>
    <script src="wasm_exec.js"></script>
    <script>
        WebAssembly API 等... 略
    </script>

    <button onClick="run();" id="runButton" disabled>Run</button>
    <div id="c1">Hello, WebAssembly!</div>
</body>

</html>

innerHTML
package main

import "syscall/js"

func main() {
    window := js.Global()                       // 获取全局的 window
    doc := window.Get("document")               // 相当于 window.document
    c1 := doc.Call("getElementById", "c1")      // 相当于 document.getElementById('c1')
    innerHTML := c1.Get("innerHTML").String()   // 相当于 c1.innerHTML
    println(innerHTML)
}

这边特意使用数个变量，代逐一对照获取的各是哪个 JavaScript 值，实际上当然可以直接写成底下：

package main

import "syscall/js"

func main() {
    innerHTML :=
        js.Global().
            Get("document").
            Call("getElementById", "c1").
            Get("innerHTML").
            String()
    println(innerHTML)
}

document.getElementById("c1").innerHTMLc1innerHTML
Go 调用 JavaScript
alert
package main

import "syscall/js"

func main() {
    alert := js.Global().Get("alert")
    // 相当于 alert('Hello, WebAssembly!')
    alert.Invoke("Hello, WebAssembly!")
}

在编译为 WebAssembly、使用浏览器连线至网页之后，按下 Run 按钮，会令浏览器出现警告对话框：

Go 调用 JavaScript

因此，如果有个自定义的 JavaScript 函数，而你想在 Go 中调用它，就是看看，那个函数是在哪个对象之上，想办法获取该对象，之后就可以加以调用了，例如：

<!doctype html>
<!--
Copyright 2018 The Go Authors. All rights reserved.
Use of this source code is governed by a BSD-style
license that can be found in the LICENSE file.
-->
<html>

<head>
    <meta charset="utf-8">
    <title>Go wasm</title>
</head>

<body>
    <script src="wasm_exec.js"></script>
    <script>
        WebAssembly API 等... 略
    </script>
    <script>
        function hi_wasm(name) {
            document.getElementById('c1').innerHTML = 'Hi, ' + name;
        }
    </script>

    <button onClick="run();" id="runButton" disabled>Run</button>
    <div id="c1">Hello, WebAssembly!</div>
</body>

</html>

hi_wasmwindow
package main

import "syscall/js"

func main() {
    hi_wasm := js.Global().Get("hi_wasm")
    hi_wasm.Invoke("WebAssembly")
}

c1
Invokejs.ValueInvokejs.Value