PureBasic
PureBasic
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 PureBasic Downloads
IncludeFile "CkStringTable.pb"
IncludeFile "CkStringBuilder.pb"
IncludeFile "CkSCard.pb"
IncludeFile "CkJsonObject.pb"
Procedure ChilkatExample()
success.i = 0
; This example requires the Chilkat API to have been previously unlocked.
; See Global Unlock Sample for sample code.
scard.i = CkSCard::ckCreate()
If scard.i = 0
Debug "Failed to create object."
ProcedureReturn
EndIf
; First establish a context to the PC/SC Resource Manager
success = CkSCard::ckEstablishContext(scard,"user")
If success = 0
Debug CkSCard::ckLastErrorText(scard)
CkSCard::ckDispose(scard)
ProcedureReturn
EndIf
; 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.
json.i = CkJsonObject::ckCreate()
If json.i = 0
Debug "Failed to create object."
ProcedureReturn
EndIf
success = CkSCard::ckFindSmartcards(scard,json)
If success = 0
Debug CkSCard::ckLastErrorText(scard)
CkSCard::ckDispose(scard)
CkJsonObject::ckDispose(json)
ProcedureReturn
EndIf
; 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"
; }
; ]
; }
CkJsonObject::setCkEmitCompact(json, 0)
Debug CkJsonObject::ckEmit(json)
Debug " "
; We can iterate over the JSON to find the readers with a smart card already inserted..
name.s
sbState.i = CkStringBuilder::ckCreate()
If sbState.i = 0
Debug "Failed to create object."
ProcedureReturn
EndIf
i.i = 0
count_i.i = CkJsonObject::ckSizeOfArray(json,"reader")
While i < count_i
CkJsonObject::setCkI(json, i)
name = CkJsonObject::ckStringOf(json,"reader[i].name")
CkStringBuilder::ckClear(sbState)
CkJsonObject::ckStringOfSb(json,"reader[i].state",sbState)
If CkStringBuilder::ckContains(sbState,"present",1) = 1
Debug name + " has a smart card inserted."
Else
Debug name + " does not have a smart card inserted."
EndIf
i = i + 1
Wend
Debug " "
; 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.
stReaders.i = CkStringTable::ckCreate()
If stReaders.i = 0
Debug "Failed to create object."
ProcedureReturn
EndIf
success = CkSCard::ckListReaders(scard,stReaders)
If success = 0
Debug CkSCard::ckLastErrorText(scard)
CkSCard::ckDispose(scard)
CkJsonObject::ckDispose(json)
CkStringBuilder::ckDispose(sbState)
CkStringTable::ckDispose(stReaders)
ProcedureReturn
EndIf
; Show the reader names..
numReaders.i = CkStringTable::ckCount(stReaders)
i = 0
While i < numReaders
Debug Str(i) + ": " + CkStringTable::ckStringAt(stReaders,i)
i = i + 1
Wend
; 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.
json2.i = CkJsonObject::ckCreate()
If json2.i = 0
Debug "Failed to create object."
ProcedureReturn
EndIf
success = CkSCard::ckGetStatusChange(scard,30000,stReaders,json2)
If success = 0
Debug CkSCard::ckLastErrorText(scard)
CkSCard::ckDispose(scard)
CkJsonObject::ckDispose(json)
CkStringBuilder::ckDispose(sbState)
CkStringTable::ckDispose(stReaders)
CkJsonObject::ckDispose(json2)
ProcedureReturn
EndIf
Debug " "
; Let's see what happened...
CkJsonObject::setCkEmitCompact(json2, 0)
Debug CkJsonObject::ckEmit(json2)
Debug " "
; 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...
changed.i
state.s
atr.s
numChanged.i = CkJsonObject::ckIntOf(json2,"numChanged")
Debug "number of readers with a changed state: " + Str(numChanged)
i = 0
count_i = CkJsonObject::ckSizeOfArray(json2,"reader")
While i < count_i
CkJsonObject::setCkI(json2, i)
changed = CkJsonObject::ckBoolOf(json2,"reader[i].changed")
If changed = 1
name = CkJsonObject::ckStringOf(json2,"reader[i].name")
state = CkJsonObject::ckStringOf(json2,"reader[i].state")
Debug "Changed: "
Debug " reader name: " + name
Debug " new state: " + state
; If a card is now in this reader, we should have the ATR of the card..
If CkJsonObject::ckHasMember(json2,"reader[i].atr") = 1
atr = CkJsonObject::ckStringOf(json2,"reader[i].atr")
Debug " ATR of card inserted into this reader: " + atr
EndIf
EndIf
i = i + 1
Wend
; 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 = CkSCard::ckReleaseContext(scard)
If success = 0
Debug CkSCard::ckLastErrorText(scard)
EndIf
CkSCard::ckDispose(scard)
CkJsonObject::ckDispose(json)
CkStringBuilder::ckDispose(sbState)
CkStringTable::ckDispose(stReaders)
CkJsonObject::ckDispose(json2)
ProcedureReturn
EndProcedure