(C) Find and Update an XML Attribute Value

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Demonstrates how to find an element in XML with a specified attribute name and then update the attribute value.

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#include <C_CkXml.h>
#include <C_CkStringBuilder.h>

void ChilkatSample(void)
    {
    HCkXml xml1;
    HCkXml xml2;
    const char *phrase_id;
    const char *phrase_value;
    HCkStringBuilder sbPath;
    int i;
    int count_i;

    // Let's say you have 2 XML files with identical structures as shown directly below,
    // and you wish to update the values in the 1st XML file with those in the 2nd XML file.

    // <global>
    //     <phrase id="2FADisabled" value="2factor authentication disabled"/>
    //     <phrase id="2FAEnabled" value="2factor authentication enabled"/>
    //     <phrase id="2FAResetFailed" value="Failed to disable two factor authentication"/>
    // </global>

    // <global>
    //     <phrase id="2FAResetFailed" value="Failed to reset two factor authentication"/>
    //     <phrase id="2FADisabled" value="2FA authentication disabled"/>
    //     <phrase id="2FAEnabled" value="2FA authentication enabled"/>
    // </global>

    // First, initialize each of the Chilkat XML objects.
    // These could be loaded from files, but we'll just create them manually for this example..

    xml1 = CkXml_Create();
    CkXml_putTag(xml1,"global");
    CkXml_UpdateAttrAt(xml1,"phrase",TRUE,"id","2FADisabled");
    CkXml_UpdateAttrAt(xml1,"phrase",TRUE,"value","2factor authentication disabled");
    CkXml_UpdateAttrAt(xml1,"phrase[1]",TRUE,"id","2FAEnabled");
    CkXml_UpdateAttrAt(xml1,"phrase[1]",TRUE,"value","2factor authentication enabled");
    CkXml_UpdateAttrAt(xml1,"phrase[2]",TRUE,"id","2FAResetFailed");
    CkXml_UpdateAttrAt(xml1,"phrase[2]",TRUE,"value","Failed to disable two factor authentication");

    xml2 = CkXml_Create();
    CkXml_putTag(xml2,"global");
    CkXml_UpdateAttrAt(xml2,"phrase",TRUE,"id","2FAResetFailed");
    CkXml_UpdateAttrAt(xml2,"phrase",TRUE,"value","Failed to reset two factor authentication");
    CkXml_UpdateAttrAt(xml2,"phrase[1]",TRUE,"id","2FADisabled");
    CkXml_UpdateAttrAt(xml2,"phrase[1]",TRUE,"value","2FA authentication disabled");
    CkXml_UpdateAttrAt(xml2,"phrase[2]",TRUE,"id","2FAEnabled");
    CkXml_UpdateAttrAt(xml2,"phrase[2]",TRUE,"value","2FA authentication enabled");

    // Iterate over attribute values in xml2 and update the same in xml1.

    sbPath = CkStringBuilder_Create();

    i = 0;
    count_i = CkXml_NumChildrenHavingTag(xml2,"phrase");
    while (i < count_i) {
        CkXml_putI(xml2,i);
        phrase_id = CkXml_chilkatPath(xml2,"phrase[i]|(id)");
        phrase_value = CkXml_chilkatPath(xml2,"phrase[i]|(value)");

        // Notice how the UpdateAttrAt method's 1st argument is a Chilkat path -- which is an expression
        // to find the location of the XML element to be updated.
        // Here we create a path of the form "/A/tagName,attributeName,attributeValuePattern", which means
        // find the direct descendent of xml2 having tag=tagName, with an attribute=attributeName where the attribute value
        // matches the attributeValuePattern.  If attributeValuePattern does not contain a "*", then it must match directly.
        // We'll build a Chilkat path such as "/A/phrase,id,2FADisabled"
        CkStringBuilder_SetString(sbPath,"/A/phrase,id,");
        CkStringBuilder_Append(sbPath,phrase_id);

        // This assumes the corresponding element exists in xml1.
        CkXml_UpdateAttrAt(xml1,CkStringBuilder_getAsString(sbPath),TRUE,"value",phrase_value);

        i = i + 1;
    }

    // Now see how xml1 has been updated..
    printf("%s\n",CkXml_getXml(xml1));


    CkXml_Dispose(xml1);
    CkXml_Dispose(xml2);
    CkStringBuilder_Dispose(sbPath);

    }