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VB.NET Requires Chilkat v11.7.0+

Validate a QR Code Request

See more QR Code Examples

Demonstrates the validate operation, which examines a request without producing anything. The scope says how far to look: definition checks the options, capacity also checks that the data fits a QR symbol, and layout also checks the rendered size against the limits. The response has a validationStatus of valid or invalid, a list of checks, and findings[] describing what is wrong. A request that cannot be understood at all, such as one with a misspelled option, still makes the call fail in the usual way.

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VB.NET
Dim success As Boolean = False

'  This example requires the Chilkat API to have been previously unlocked.
'  See Global Unlock Sample for sample code.

Dim fmt As New Chilkat.Formats
Dim jsonOut As New Chilkat.JsonObject
Dim i As Integer
Dim n As Integer

Dim json As New Chilkat.JsonObject
json.UpdateString("target","symbol")
json.UpdateString("validation.scope","capacity")
json.UpdateString("payload.text","https://www.chilkatsoft.com/barcode_overview.asp")

success = fmt.QrCode("validate",json,jsonOut)
If (success = False) Then
    Debug.WriteLine(fmt.LastErrorText)
    Exit Sub
End If

Debug.WriteLine("status: " & jsonOut.StringOf("validationStatus"))
n = jsonOut.SizeOfArray("checks")
For i = 0 To n - 1
    jsonOut.I = i
    Debug.WriteLine("  " & jsonOut.StringOf("checks[i].name") & ": " & jsonOut.StringOf("checks[i].status"))
Next

'  The same text does not fit version 2 at error-correction level H.
json.UpdateInt("encoding.qr.maxVersion",2)
json.UpdateString("encoding.qr.errorCorrection","H")

success = fmt.QrCode("validate",json,jsonOut)
If (success = False) Then
    Debug.WriteLine(fmt.LastErrorText)
    Exit Sub
End If

Debug.WriteLine("status: " & jsonOut.StringOf("validationStatus"))
n = jsonOut.SizeOfArray("checks")
For i = 0 To n - 1
    jsonOut.I = i
    Debug.WriteLine("  " & jsonOut.StringOf("checks[i].name") & ": " & jsonOut.StringOf("checks[i].status"))
Next
n = jsonOut.SizeOfArray("findings")
For i = 0 To n - 1
    jsonOut.I = i
    Debug.WriteLine("finding: " & jsonOut.StringOf("findings[i].code") & " at " & jsonOut.StringOf("findings[i].path"))
    Debug.WriteLine("  " & jsonOut.StringOf("findings[i].message"))
Next

'  Sample output:

'  status: valid
'    definition: passed
'    capacity: passed
'    layout: notApplicable
'  status: invalid
'    definition: passed
'    capacity: failed
'    layout: notApplicable
'  finding: capacityExceeded at /payload
'    the payload does not fit any admitted QR version at the selected error-correction level