我可以在Spidermonkey中执行Javascript函数并获取返回值吗？ [英] Can I execute a Javascript function inside Spidermonkey and get the return value?

问题描述

我刚刚开始使用Delphi和Spidermonkey。以前我会将一个网页加载到TWebBrowser组件中，并与加载的网页中的Javascript代码进行交互。这很麻烦，因为要将值返回给delphi，我必须通过Javascript代码将它们加载到DOM对象中，然后从Delphi中检查DOM以找到该对象并访问它的 value 属性。

I'm just getting into using Delphi with Spidermonkey. Previously I would load a web page into a TWebBrowser component and interact with the Javascript code in the loaded web page. This was messy because to return values back to delphi I had to load them into a DOM object via the Javascript code and then inspect the DOM from Delphi to find that object and access it's value property.

使用Spidermonkey，我可以执行特定的Javascript函数并轻松获取返回值并直接返回Delphi吗？如果是这样，请指出一个有用的快速代码示例。 Spidermonkey附带的3个样本似乎没有进入这个。

With Spidermonkey, can I execute a specific Javascript function and get the return value easily and directly back into Delphi? If so, please point me to a quick code example that would be helpful. The 3 samples that came with Spidermonkey don't seem to get into this.

推荐答案

>使用Spidermonkey，我可以吗？执行一个特定的Javascript函数并轻松获得返回值并直接返回Delphi？

是的，这是可能的。示例与Delphi XE2 / XE4兼容。

Yes, it possible. Sample compatible with Delphi XE2/XE4.

var
    recFunction,
    recReturnValue,
    recJSVar        : jsval;

........

//-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
//-=- Find entry point to function.
//-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-

if JS_LookupProperty (TSMJSEngine.Context, TSMJSEngine.Global.JSObject, PAnsiChar (AnsiString (strFunctionToRun)), @recFunction) <> js_true then
begin
    //-=- Everything very bad :)
end;

if recFunction.asPtr = nil then
begin
    //-=- Everything very bad :)
end;

//-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
//-=- Call function 
//-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-

if JS_CallFunctionValue (TSMJSEngine.Context, TSMJSEngine.Global.JSObject, recFunction, 0, nil, @recReturnValue) = Integer (false) then
begin
    //-=- Everything very bad :)
end;

//-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
//-=- Get returning result (type: string).
//-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-

strResult := JSValToString (TSMJSEngine.Context, recReturnValue);

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