Visual FoxPro

JavaScript console using Callbacks

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Demonstrates console output using Chilkat JavaScript with callbacks. Visual FoxPro

LOCAL lnSuccess
LOCAL loSbScript
LOCAL loJs
LOCAL loResult

lnSuccess = 0

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

*  Load the JavaScript from a file.
loSbScript = CreateObject('Chilkat.StringBuilder')
lnSuccess = loSbScript.LoadFile("qa_data/js_tests/test_console.js","utf-8")
IF (lnSuccess = 0) THEN
    ? loSbScript.LastErrorText
    RELEASE loSbScript
    CANCEL
ENDIF

loJs = CreateObject('Chilkat.Js')
jsEventHandler = CreateObject("jsEvents")
EventHandler(loJs,jsEventHandler)
loResult = CreateObject('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.
lnSuccess = loJs.Eval(loSbScript,loResult)
IF (lnSuccess = 0) THEN
    ? loSbScript.LastErrorText
    RELEASE loSbScript
    RELEASE loJs
    RELEASE loResult
    CANCEL
ENDIF

*  We can look at the result, which is "undefined", which is normal and expected.
? loResult.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"}

RELEASE loSbScript
RELEASE loJs
RELEASE loResult

[K]DEFINE CLASS[/K] jsEvents [K]AS SESSION OLEPUBLIC[/K]
[K]IMPLEMENTS[/K] _IChilkatEvents [K]IN[/K] "Chilkat.Js"

[K]PROCEDURE[/K] _IChilkatEvents_AbortCheck(abort [K]As[/K] [K]Number[/K])
    [C]* Application code goes here...[/C]

[K]ENDPROC[/K]

[K]PROCEDURE[/K] _IChilkatEvents_BinaryData(data [K]As[/K] [K]Variant[/K])
    [C]* Application code goes here...[/C]

[K]ENDPROC[/K]

[K]PROCEDURE[/K] _IChilkatEvents_PercentDone(pctDone [K]As[/K] [K]Number[/K], abort [K]As[/K] [K]Number[/K])
    [C]* Application code goes here...[/C]

[K]ENDPROC[/K]

[K]PROCEDURE[/K] _IChilkatEvents_ProgressInfo(name [K]As[/K] [K]String[/K], value [K]As[/K] [K]String[/K])
    [C]* Application code goes here...[/C]
    ? name + ": " + value
[K]ENDPROC[/K]

[K]PROCEDURE[/K] _IChilkatEvents_TaskCompleted(task [K]As[/K] [K]Generic[/K])
    [C]* Application code goes here...[/C]

[K]ENDPROC[/K]

[K]PROCEDURE[/K] _IChilkatEvents_TextData(data [K]As[/K] [K]String[/K])
    [C]* Application code goes here...[/C]

[K]ENDPROC[/K]


[K]ENDDEFINE[/K]

JavaScript

// Chilkat Js console emits CRLF line endings on Windows, and LF line endings on non-Windows.

console.log("Hello %s, %d, %f", "World", 248, 12.05);
// Output: Hello World, 248, 12.05

// If there are more arguments than the number of specifiers, the extra arguments are output, separated by spaces:
console.error('%s:%s', 'foo', 'bar', 'baz');
// Output: foo:bar baz

// If the first argument does not contain a valid format specifier, outputs a string that is the concatenation of all arguments separated by spaces:
console.warn(1,2,3);
// Output: 1 2 3

//If only one argument is passed, it is returned as it is without any formatting:
console.log("%% %s");
// Output: %% %s

const myApp = {
    appName: "Example",
    version: 1.0,
    isDebug: true,
    supportedTypes: ["string", "number", "object"],
    settings: {
       "maxWidgets": 1024,
        allowIO: true
    }
};

// %O: Emits the same as JSON.stringify(myConfig, null, 2)
console.log("myApp: %O", myApp);
// Output:
// myApp: {
//   "appName": "Example",
//   "version": 1,
//   "isDebug": true,
//   "supportedTypes": [
//     "string",
//     "number",
//     "object"
//   ],
//   "settings": {
//     "maxWidgets": 1024,
//     "allowIO": true
//   }
// }

console.log("App: %s (Version %d)", myApp.appName, myApp.version);
// Output: App: Example (Version 1)