C#中v8引擎

V8引擎的样例。来源于ClearScript的github上的例子。

 

以下例子足以满足大部分需求。

using System;
using Microsoft.ClearScript;
using Microsoft.ClearScript.JavaScript;

using Microsoft.ClearScript.V8;


// create a script engine

using (var engine = new V8ScriptEngine())

{

    // expose a host type

    engine.AddHostType("Console", typeof(Console));

    engine.Execute("Console.WriteLine('{0} is an interesting number.', Math.PI)");

 

    // expose a host object

    engine.AddHostObject("random", new Random());

    engine.Execute("Console.WriteLine(random.NextDouble())");

 

    // expose entire assemblies

    engine.AddHostObject("lib", new HostTypeCollection("mscorlib", "System.Core"));

    engine.Execute("Console.WriteLine(lib.System.DateTime.Now)");

 

    // create a host object from script

    engine.Execute(@"

        birthday = new lib.System.DateTime(2007, 5, 22);

        Console.WriteLine(birthday.ToLongDateString());

    ");

 

    // use a generic class from script

    engine.Execute(@"

        Dictionary = lib.System.Collections.Generic.Dictionary;

        dict = new Dictionary(lib.System.String, lib.System.Int32);

        dict.Add('foo', 123);

    ");

 

    // call a host method with an output parameter

    engine.AddHostObject("host", new HostFunctions());

    engine.Execute(@"

        intVar = host.newVar(lib.System.Int32);

        found = dict.TryGetValue('foo', intVar.out);

        Console.WriteLine('{0} {1}', found, intVar);

    ");

 

    // create and populate a host array

    engine.Execute(@"

        numbers = host.newArr(lib.System.Int32, 20);

        for (var i = 0; i < numbers.Length; i++) { numbers[i] = i; }

        Console.WriteLine(lib.System.String.Join(', ', numbers));

    ");

 

    // create a script delegate

    engine.Execute(@"

        Filter = lib.System.Func(lib.System.Int32, lib.System.Boolean);

        oddFilter = new Filter(function(value) {

            return (value & 1) ? true : false;

        });

    ");

 

    // use LINQ from script

    engine.Execute(@"

        oddNumbers = numbers.Where(oddFilter);

        Console.WriteLine(lib.System.String.Join(', ', oddNumbers));

    ");

 

    // use a dynamic host object

    engine.Execute(@"

        expando = new lib.System.Dynamic.ExpandoObject();

        expando.foo = 123;

        expando.bar = 'qux';

        delete expando.foo;

    ");

 

    // call a script function

    engine.Execute("function print(x) { Console.WriteLine(x); }");

    engine.Script.print(DateTime.Now.DayOfWeek);

 

    // examine a script object

    engine.Execute("person = { name: 'Fred', age: 5 }");

    Console.WriteLine(engine.Script.person.name);

 

    // read a JavaScript typed array

    engine.Execute("values = new Int32Array([1, 2, 3, 4, 5])");

    var values = (ITypedArray<int>)engine.Script.values;

    Console.WriteLine(string.Join(", ", values.ToArray()));

}