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DataFlex

MX Lookup Mail Server Domain by Email Address

How to find the mail server for a given email address. Returns the domain name of the primary mail server.

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DataFlex
Use ChilkatAx-win32.pkg

Procedure Test
    Boolean iSuccess
    Handle hoDns
    Variant vJson
    Handle hoJson
    String sEmailAddr
    Integer i
    Integer iCount_i
    String sDomain
    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(cComChilkatDns)) To hoDns
    If (Not(IsComObjectCreated(hoDns))) Begin
        Send CreateComObject of hoDns
    End
    Get Create (RefClass(cComChilkatJsonObject)) To hoJson
    If (Not(IsComObjectCreated(hoJson))) Begin
        Send CreateComObject of hoJson
    End

    Move "bob@example.com" To sEmailAddr

    // This gets all MX domains for an email address.  (Typically one domain.)
    // The preferred domain will be at index 0 (see below).
    Get pvComObject of hoJson to vJson
    Get ComQuery Of hoDns "MX" sEmailAddr vJson To iSuccess
    If (iSuccess = False) Begin
        Get ComLastErrorText Of hoDns To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    Move 0 To i
    Get ComSizeOfArray Of hoJson "answer.mx" To iCount_i
    While (i < iCount_i)
        Set ComI Of hoJson To i
        Get ComStringOf Of hoJson "answer.mx[i].domain" To sDomain
        Showln sDomain
        Move (i + 1) To i
    Loop



End_Procedure