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DataFlex

Sign a PDF using Certificate from Windows Certificate Store

See more PDF Signatures Examples

This example demonstrates how to a sign a PDF using a certificate from the Windows Certificate Store.

Note: This example requires Chilkat v9.5.0.85 or greater.

Chilkat DataFlex Downloads

DataFlex
Use ChilkatAx-win32.pkg

Procedure Test
    Boolean iSuccess
    Handle hoPdf
    Variant vJson
    Handle hoJson
    Variant vCert
    Handle hoCert
    String sTemp1

    Move False To iSuccess

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

    Get Create (RefClass(cComChilkatPdf)) To hoPdf
    If (Not(IsComObjectCreated(hoPdf))) Begin
        Send CreateComObject of hoPdf
    End

    // Load a PDF to be signed.
    // The "hello.pdf" is available at https://chilkatsoft.com/hello.pdf
    Get ComLoadFile Of hoPdf "qa_data/pdf/hello.pdf" To iSuccess
    If (iSuccess = False) Begin
        Get ComLastErrorText Of hoPdf To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // Options for signing are specified in JSON.
    Get Create (RefClass(cComChilkatJsonObject)) To hoJson
    If (Not(IsComObjectCreated(hoJson))) Begin
        Send CreateComObject of hoJson
    End

    // In most cases, the signingCertificateV2 and signingTime attributes are required.
    Get ComUpdateInt Of hoJson "signingCertificateV2" 1 To iSuccess
    Get ComUpdateInt Of hoJson "signingTime" 1 To iSuccess

    // Put the signature on page 1, top left
    Get ComUpdateInt Of hoJson "page" 1 To iSuccess
    Get ComUpdateString Of hoJson "appearance.y" "top" To iSuccess
    Get ComUpdateString Of hoJson "appearance.x" "left" To iSuccess

    // Use a font scale of 10.0
    Get ComUpdateString Of hoJson "appearance.fontScale" "10.0" To iSuccess

    // In this example, the appearance of the digital signature will contain three lines:
    // 1) The signing certificate's common name
    // 2) The current date/time
    // 3) Some arbitrary text.
    // The keyword "cert_cn" is replaced with the Certificate's Subject Common Name.
    // The keyword "current_dt" is replaced with the current date/time.
    // Any number of appearance text lines can be added.
    Get ComUpdateString Of hoJson "appearance.text[0]" "Digitally signed by: cert_cn" To iSuccess
    Get ComUpdateString Of hoJson "appearance.text[1]" "current_dt" To iSuccess
    Get ComUpdateString Of hoJson "appearance.text[2]" "The crazy brown fox jumps over the lazy dog." To iSuccess

    // Load a certificate by specifying the common name ("CN" part of the certificate's Subject)
    Get Create (RefClass(cComChilkatCert)) To hoCert
    If (Not(IsComObjectCreated(hoCert))) Begin
        Send CreateComObject of hoCert
    End
    Get ComLoadByCommonName Of hoCert "Xyz Widgets, Inc." To iSuccess
    If (iSuccess = False) Begin
        Get ComLastErrorText Of hoCert To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // Tell the pdf object to use the certificate for signing.
    Get pvComObject of hoCert to vCert
    Get ComSetSigningCert Of hoPdf vCert To iSuccess
    If (iSuccess = False) Begin
        Get ComLastErrorText Of hoPdf To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    Get pvComObject of hoJson to vJson
    Get ComSignPdf Of hoPdf vJson "qa_output/hello_signed.pdf" To iSuccess
    If (iSuccess = False) Begin
        Get ComLastErrorText Of hoPdf To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    Showln "The PDF has been successfully cryptographically signed."


End_Procedure