PureBasic

JavaScript console

See more JavaScript Examples

Demonstrates console output using Chilkat JavaScript. PureBasic

IncludeFile "CkJs.pb"
IncludeFile "CkStringBuilder.pb"
IncludeFile "CkJsonObject.pb"

Procedure ChilkatExample()

    success.i = 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.
    sbScript.i = CkStringBuilder::ckCreate()
    If sbScript.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    success = CkStringBuilder::ckLoadFile(sbScript,"qa_data/js_tests/test_console.js","utf-8")
    If success = 0
        Debug CkStringBuilder::ckLastErrorText(sbScript)
        CkStringBuilder::ckDispose(sbScript)
        ProcedureReturn
    EndIf

    js.i = CkJs::ckCreate()
    If js.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    result.i = CkJsonObject::ckCreate()
    If result.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    ;  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 = CkJs::ckEval(js,sbScript,result)
    If success = 0
        Debug CkStringBuilder::ckLastErrorText(sbScript)
        CkStringBuilder::ckDispose(sbScript)
        CkJs::ckDispose(js)
        CkJsonObject::ckDispose(result)
        ProcedureReturn
    EndIf

    ;  We can look at the result, which is "undefined", which is normal and expected.
    Debug CkJsonObject::ckEmit(result)
    ;  The result JSON is: {"type":"undefined","value":"undefined"}

    ;  The console output is retrieved by calling ConsoleOutputSb
    sbOut.i = CkStringBuilder::ckCreate()
    If sbOut.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    CkJs::ckConsoleOutputSb(js,sbOut)
    Debug CkStringBuilder::ckGetAsString(sbOut)


    CkStringBuilder::ckDispose(sbScript)
    CkJs::ckDispose(js)
    CkJsonObject::ckDispose(result)
    CkStringBuilder::ckDispose(sbOut)


    ProcedureReturn
EndProcedure

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.log('%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.log(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: Chilkat Js (Version 1)