go - go-duktape 调用函数的例子

Question

go-duktape存储库没有“问题”部分或无论如何都可以寻求帮助。

自述文件中没有有用的示例。

我正在尝试在 javascript 文件中定义一个函数（带有参数和返回值）并从 go 调用这个函数。

Javascript 文件：

function hello(name, age){
    return "Hello " + name + " you are " + age;
}

事情的进展会是什么样子？

Answer 1

This is another way of doing

package main

import (
  "github.com/olebedev/go-duktape"
  "fmt"
  "time"
)

func print_name (c *duktape.Context) int {
  c.PushThis()
  c.GetPropString(-1, "name")
  fmt.Printf( "My name is: %v\n", c.SafeToString(-1) )
  return 0
}

func myobject_constructor (c *duktape.Context) int {

  if c.IsConstructorCall() == false {
    return duktape.ErrRetType
  }

  c.PushThis()
  c.Dup( 0 )
  c.PutPropString(-2, "name")
  return 0
}

func main() {

  start := time.Now()

  ctx := duktape.New()

  /*
  function MyObject(name) {
      // When called as new MyObject(), "this" will be bound to the default
      // instance object here.

      this.name = name;

      // Return undefined, which causes the default instance to be used.
  }

  // For an ECMAScript function an automatic MyObject.prototype value will be
  // set.  That object will also have a .constructor property pointing back to
  // Myobject.  You can add instance methods to MyObject.prototype.

  MyObject.prototype.printName = function () {
      print('My name is: ' + this.name);
  };

  var obj = new MyObject('test object');
  obj.printName();  // My name is: test object
  */

  ctx.PushGoFunction(myobject_constructor)
  ctx.PushObject()
  ctx.PushGoFunction(print_name)
  ctx.PutPropString(-2, "printName")
  ctx.PutPropString(-2, "prototype")
  ctx.PutGlobalString("MyObject")

  /*
  make this
  */
  ctx.EvalString( "var a = new MyObject('test name one');" )
  ctx.EvalString( "a.printName();" )


  /*
  or make this
  */
  ctx.EvalString( "new MyObject('test name two');" )
  ctx.GetPropString(-1, "printName")
  ctx.Dup(-2)
  ctx.CallMethod(0)
  ctx.Pop()
  ctx.Pop()
  ctx.GetGlobalString("MyObject")


  ctx.DestroyHeap()
  elapsed := time.Since(start)
  fmt.Printf("total time: %s\n", elapsed)
}

Answer 2

这是我第一次使用此代码，可能还有另一种方法可以在不使用 json 的情况下获取整个对象，但到目前为止，我还没有找到它。我希望我对你有所帮助。

包主

import (
  "github.com/olebedev/go-duktape"
  "fmt"
  "time"
)

func main() {
  start := time.Now()
  ctx := duktape.New()
  ctx.PushGlobalGoFunction("log", func(c *duktape.Context) int {
    i := -1
    for {

      if c.GetType(i).IsNone() == true {
        break
      }

      if i < -100 {
        break
      }

      if c.GetType(i).IsString() == true {
        fmt.Println(c.SafeToString(i))
      }

      if c.GetType(i).IsNumber() == true {
        fmt.Println(c.GetNumber(i))
      }

      if c.GetType(i).IsObject() == true {
        c.ToObject(i)
        fmt.Printf( "%v\n", c.JsonEncode(i) )
      }

      i -= 1
    }

    return 0
  })
  ctx.PevalString(`log({'hello':'word'})`)
  ctx.DestroyHeap()
  elapsed := time.Since(start)
  fmt.Printf("total time: %s\n", elapsed)
}