(Unicode 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_CkXmlW.h>
#include <C_CkStringBuilderW.h>

void ChilkatSample(void)
    {
    HCkXmlW xml1;
    HCkXmlW xml2;
    const wchar_t *phrase_id;
    const wchar_t *phrase_value;
    HCkStringBuilderW 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 = CkXmlW_Create();
    CkXmlW_putTag(xml1,L"global");
    CkXmlW_UpdateAttrAt(xml1,L"phrase",TRUE,L"id",L"2FADisabled");
    CkXmlW_UpdateAttrAt(xml1,L"phrase",TRUE,L"value",L"2factor authentication disabled");
    CkXmlW_UpdateAttrAt(xml1,L"phrase[1]",TRUE,L"id",L"2FAEnabled");
    CkXmlW_UpdateAttrAt(xml1,L"phrase[1]",TRUE,L"value",L"2factor authentication enabled");
    CkXmlW_UpdateAttrAt(xml1,L"phrase[2]",TRUE,L"id",L"2FAResetFailed");
    CkXmlW_UpdateAttrAt(xml1,L"phrase[2]",TRUE,L"value",L"Failed to disable two factor authentication");

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

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

    sbPath = CkStringBuilderW_Create();

    i = 0;
    count_i = CkXmlW_NumChildrenHavingTag(xml2,L"phrase");
    while (i < count_i) {
        CkXmlW_putI(xml2,i);
        phrase_id = CkXmlW_chilkatPath(xml2,L"phrase[i]|(id)");
        phrase_value = CkXmlW_chilkatPath(xml2,L"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"
        CkStringBuilderW_SetString(sbPath,L"/A/phrase,id,");
        CkStringBuilderW_Append(sbPath,phrase_id);

        // This assumes the corresponding element exists in xml1.
        CkXmlW_UpdateAttrAt(xml1,CkStringBuilderW_getAsString(sbPath),TRUE,L"value",phrase_value);

        i = i + 1;
    }

    // Now see how xml1 has been updated..
    wprintf(L"%s\n",CkXmlW_getXml(xml1));


    CkXmlW_Dispose(xml1);
    CkXmlW_Dispose(xml2);
    CkStringBuilderW_Dispose(sbPath);

    }