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Visual Basic 6.0

JavaScript console using Callbacks

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Demonstrates console output using Chilkat JavaScript with callbacks.

Chilkat Visual Basic 6.0 Downloads

Visual Basic 6.0
Dim WithEvents js As  ChilkatJs

' ProgressInfo callback method.
Private Sub js_ProgressInfo(ByVal name As String, ByVal value As String)
    Debug.Print name & ": " & value
End Sub

private Sub ChilkatExample()

    Dim success As Long
    success = 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.
    Dim sbScript As New ChilkatStringBuilder
    success = sbScript.LoadFile("qa_data/js_tests/test_console.js","utf-8")
    If (success = 0) Then
        Debug.Print sbScript.LastErrorText
        Exit Sub
    End If

    Set  js = New ChilkatJs

    Dim result As New ChilkatJsonObject

    ' 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 = 0) Then
        Debug.Print sbScript.LastErrorText
        Exit Sub
    End If

    ' We can look at the result, which is "undefined", which is normal and expected.
    Debug.Print 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"}

End Sub