Classic ASP
Classic ASP
PC/SC Wait for Smart Card Status Change (Inserted, Removed from Reader, etc.)
See more SCard Examples
Demonstrates how to synchronously wait for a status change, such as for a smart card to be inserted into a reader, or removed from a reader.Note: This functionality was introduced in Chilkat v9.5.0.87.
Chilkat Classic ASP Downloads
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
</head>
<body>
<%
success = 0
' This example requires the Chilkat API to have been previously unlocked.
' See Global Unlock Sample for sample code.
set scard = Server.CreateObject("Chilkat.SCard")
' First establish a context to the PC/SC Resource Manager
success = scard.EstablishContext("user")
If (success = 0) Then
Response.Write "<pre>" & Server.HTMLEncode( scard.LastErrorText) & "</pre>"
Response.End
End If
' First we'll examine the state of all connected readers to see which have smartcards already inserted..
' Get JSON containing information about the smartcards currently inserted into readers.
' This also includes information about USB security tokens.
set json = Server.CreateObject("Chilkat.JsonObject")
success = scard.FindSmartcards(json)
If (success = 0) Then
Response.Write "<pre>" & Server.HTMLEncode( scard.LastErrorText) & "</pre>"
Response.End
End If
' When writing this example, I have 3 smart card readers plugged into my system.
' One of them has a smart card inserted.
' Here's the JSON returned by FindSmartcards...
' {
' "reader": [
' {
' "name": "Alcor Micro USB Smart Card Reader 0",
' "state": "empty"
' },
' {
' "name": "Generic Smart Card Reader Interface 0",
' "state": "present",
' "vendorName": "Generic",
' "serialNumber": "3230303730383138303030303030303030",
' "systemName": "Generic Smart Card Reader Interface 0",
' "card": {
' "atr": "3BFC180000813180459067464A00641606F2727E00E0",
' "windows": {
' "miniDriver": "tagliov70px.dll",
' "cryptoProvider": "Microsoft Base Smart Card Crypto Provider",
' "keyStorageProvider": "Microsoft Smart Card Key Storage Provider"
' }
' }
' },
' {
' "name": "SCM Microsystems Inc. SCR33x USB Smart Card Reader 0",
' "state": "empty"
' }
' ]
' }
json.EmitCompact = 0
Response.Write "<pre>" & Server.HTMLEncode( json.Emit()) & "</pre>"
Response.Write "<pre>" & Server.HTMLEncode( " ") & "</pre>"
' We can iterate over the JSON to find the readers with a smart card already inserted..
set sbState = Server.CreateObject("Chilkat.StringBuilder")
i = 0
count_i = json.SizeOfArray("reader")
Do While i < count_i
json.I = i
name = json.StringOf("reader[i].name")
sbState.Clear
success = json.StringOfSb("reader[i].state",sbState)
If (sbState.Contains("present",1) = 1) Then
Response.Write "<pre>" & Server.HTMLEncode( name & " has a smart card inserted.") & "</pre>"
Else
Response.Write "<pre>" & Server.HTMLEncode( name & " does not have a smart card inserted.") & "</pre>"
End If
i = i + 1
Loop
Response.Write "<pre>" & Server.HTMLEncode( " ") & "</pre>"
' Now let's begin the code to wait for a change (where a smart card gets inserted or removed)
' Get the list of all readers.
set stReaders = Server.CreateObject("Chilkat.StringTable")
success = scard.ListReaders(stReaders)
If (success = 0) Then
Response.Write "<pre>" & Server.HTMLEncode( scard.LastErrorText) & "</pre>"
Response.End
End If
' Show the reader names..
numReaders = stReaders.Count
i = 0
Do While i < numReaders
Response.Write "<pre>" & Server.HTMLEncode( i & ": " & stReaders.StringAt(i)) & "</pre>"
i = i + 1
Loop
' Sample output from the above loop.
' 0: Alcor Micro USB Smart Card Reader 0
' 1: Generic Smart Card Reader Interface 0
' 2: SCM Microsystems Inc. SCR33x USB Smart Card Reader 0
'
' Synchronously wait 30 seconds for a card to be inserted or removed from any of the above readers.
set json2 = Server.CreateObject("Chilkat.JsonObject")
success = scard.GetStatusChange(30000,stReaders,json2)
If (success = 0) Then
Response.Write "<pre>" & Server.HTMLEncode( scard.LastErrorText) & "</pre>"
Response.End
End If
Response.Write "<pre>" & Server.HTMLEncode( " ") & "</pre>"
' Let's see what happened...
json2.EmitCompact = 0
Response.Write "<pre>" & Server.HTMLEncode( json2.Emit()) & "</pre>"
Response.Write "<pre>" & Server.HTMLEncode( " ") & "</pre>"
' This is what json2 contains.
' A card was inserted into the reader named "SCM Microsystems Inc. SCR33x USB Smart Card Reader 0"
' The "numChanged" indicates that one reader's status changed.
' The "changed":true indicates the reader that changed. The state is now "present".
' {
' "numChanged": 1,
' "reader": [
' {
' "name": "Alcor Micro USB Smart Card Reader 0",
' "changed": false,
' "state": "empty"
' },
' {
' "name": "Generic Smart Card Reader Interface 0",
' "changed": false,
' "state": "present",
' "atr": "3BFC180000813180459067464A00641606F2727E00E0"
' },
' {
' "name": "SCM Microsystems Inc. SCR33x USB Smart Card Reader 0",
' "changed": true,
' "state": "present",
' "atr": "3BDF96FF8131FE455A018048494443313158587300011B09"
' }
' ]
' }
' Find the reader that changed...
numChanged = json2.IntOf("numChanged")
Response.Write "<pre>" & Server.HTMLEncode( "number of readers with a changed state: " & numChanged) & "</pre>"
i = 0
count_i = json2.SizeOfArray("reader")
Do While i < count_i
json2.I = i
changed = json2.BoolOf("reader[i].changed")
If (changed = 1) Then
name = json2.StringOf("reader[i].name")
state = json2.StringOf("reader[i].state")
Response.Write "<pre>" & Server.HTMLEncode( "Changed: ") & "</pre>"
Response.Write "<pre>" & Server.HTMLEncode( " reader name: " & name) & "</pre>"
Response.Write "<pre>" & Server.HTMLEncode( " new state: " & state) & "</pre>"
' If a card is now in this reader, we should have the ATR of the card..
If (json2.HasMember("reader[i].atr") = 1) Then
atr = json2.StringOf("reader[i].atr")
Response.Write "<pre>" & Server.HTMLEncode( " ATR of card inserted into this reader: " & atr) & "</pre>"
End If
End If
i = i + 1
Loop
' The output from the above loop:
' number of readers with a changed state: 1
' Changed:
' reader name: SCM Microsystems Inc. SCR33x USB Smart Card Reader 0
' new state: present
' ATR of card inserted into this reader: 3BDF96FF8131FE455A018048494443313158587300011B09
' Applications should always release the context when finished.
success = scard.ReleaseContext()
If (success = 0) Then
Response.Write "<pre>" & Server.HTMLEncode( scard.LastErrorText) & "</pre>"
End If
%>
</body>
</html>