tinyxml parsing xml file

Question

I have a xml file like this:

<?xml version="1.0"?>

<ApplicationSettings>
    <BeamGeometry  
        Dimension="2"
        Type="fan"
        Shape="arc"
        LengthFocalPointToISOCenter="558"
        LengthISOCenterToDetector="394"
        LengthDetectorSeperation="0.98"
        LengthModuleSeperation="0.04"
        NumberModules="57" 
        NumberDetectorsPerModule="16" 
        NumberISOCenterShift="3.25" />
</ApplicationSettings>

And I'd like to use tinyxml retrieving all the values (such as 558) based on the entry name such as (LengthFocalPointToISOCenter). Here is my code, not successful yet.

int SetFanbeamGeometry(const char* filename)    
{   
    int ret = TRUE;

    TiXmlDocument doc("E:\\Projects\\iterativeRecon\\ProjectPackage\\ApplicationSettings\\ApplicationSettings.xml");

    int LengthFocalPointToISOCenter;

    if( doc.LoadFile())
    {

        TiXmlHandle hDoc(&doc);
        TiXmlElement *pRoot, *pParm;
        pRoot = doc.FirstChildElement("ApplicationSettings");
        if(pRoot)
        {
            pParm = pRoot->FirstChildElement("BeamGeometry");
            int i = 0; // for sorting the entries
            while(pParm)
            {
                pParm = pParm->NextSiblingElement("BeamGeometry");
                i++;
            }
        }
    }
    else
    {
        printf("Warning: ApplicationSettings is not loaded!");
        ret = FALSE;
    }

    return ret;
}

I am wondering how can I use tinyxml to do that? Sorry I am a first time user. and it looks confusing to me. Thanks.

Jonathan Potter · Accepted Answer · 2014-12-17T22:23:34.470

There's only one BeamGeometry child element in the snippet you've shown; the information you're trying to access are its attributes - they're not individual elements.

So you need something like this:

// ...
pParm = pRoot->FirstChildElement("BeamGeometry");
if (pParm)
{
    const char* pAttr = pParm->Attribute("LengthFocalPointToISOCenter");
    if (pAttr)
    {
        int iLengthFocalPointToISOCenter = strtoul(pAttr, NULL, 10);
        // do something with the value
    }
}

If you want to loop through all attributes, it's quite simple:

const TiXmlAttribute* pAttr = pParm->FirstAttribute();
while (pAttr)
{
    const char* name = pAttr->Name(); // attribute name
    const char* value = pAttr->Value(); // attribute value
    // do something
    pAttr = pAttr->Next();
}

Thanks. But if I want to loop through all entries? – Ono Dec 17 '14 at 22:09 — Ono, Dec 17 '14 at 22:09
@Ono: Added that to the answer. – Jonathan Potter Dec 17 '14 at 22:23 — Jonathan Potter, Dec 17 '14 at 22:23

tinyxml parsing xml file

1 Answers1