C#

JavaScript console using Callbacks

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Demonstrates console output using Chilkat JavaScript with callbacks. C#

// ProgressInfo callback method.
private void js_OnProgressInfo(object sender, Chilkat.ProgressInfoEventArgs args)
    {
    string name = args.Name;
    string value = args.Value;
    Debug.WriteLine(name + ": " + value);
    }

private void ChilkatExample()
    {
    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.
    Chilkat.StringBuilder sbScript = new Chilkat.StringBuilder();
    success = sbScript.LoadFile("qa_data/js_tests/test_console.js","utf-8");
    if (success == false) {
        Debug.WriteLine(sbScript.LastErrorText);
        return;
    }

    Chilkat.Js js = new Chilkat.Js();
    js.OnProgressInfo += js_OnProgressInfo;
    Chilkat.JsonObject result = new Chilkat.JsonObject();

    //  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) {
        Debug.WriteLine(sbScript.LastErrorText);
        return;
    }

    //  We can look at the result, which is "undefined", which is normal and expected.
    Debug.WriteLine(result.Emit());
    //  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"}

    }