C++

JavaScript console using Callbacks

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Demonstrates console output using Chilkat JavaScript with callbacks. C++

#include <CkStringBuilder.h>
#include <CkJs.h>
#include <CkJsonObject.h>

#include <CkBaseProgress.h>

class jsProgress : public CkBaseProgress {

  public:
  jsProgress() { }
  virtual ~jsProgress() { }

  void ProgressInfo(const char *name, const char *value) {
    std::cout << name << ": " << value << "\r\n";
  }

};

void ChilkatSample(void)
    {
    bool success = false;

    // This example demonstrates using the built-in console object.
    // The Javascript run in this example is shown below.

    // Load the JavaScript from a file.
    CkStringBuilder sbScript;
    success = sbScript.LoadFile("qa_data/js_tests/test_console.js","utf-8");
    if (success == false) {
        std::cout << sbScript.lastErrorText() << "\r\n";
        return;
    }

    CkJs js;
    jsProgress js_progress;
    js.put_EventCallbackObject(&js_progress);
    CkJsonObject result;

    // Run the JavaScript
    // Results (not console output) go to result.
    // Note: Eval returns the completion value of the script. This is generally the value of the last evaluated expression.
    // In this case, the last evaluated expression is console.log which does not calculate a value. Therefore, it returns undefined.
    success = js.Eval(sbScript,result);
    if (success == false) {
        std::cout << sbScript.lastErrorText() << "\r\n";
        return;
    }

    // We can look at the result, which is "undefined", which is normal and expected.
    std::cout << result.emit() << "\r\n";
    // The result JSON is: {"type":"undefined","value":"undefined"}

    // The console output is received using ProgressInfo callbacks.
    // The output is:

    // log: Hello World, 248, 12.05
    // 
    // error: foo:bar baz
    // 
    // warn: 1 2 3
    // 
    // log: %% %s
    // 
    // log: myApp: {
    //   "appName": "Example",
    //   "version": 1,
    //   "isDebug": true,
    //   "supportedTypes": [
    //     "string",
    //     "number",
    //     "object"
    //   ],
    //   "settings": {
    //     "maxWidgets": 1024,
    //     "allowIO": true
    //   }
    // }
    // 
    // log: App: myApp (Version 1)
    // 
    // {"type":"undefined","value":"undefined"}
    }