c# - vérification du contenu de l'élément XML existant et remplaçant - débordement de pile

I have a c# app that writes to XML using the following code:

     //Write last compliant elements to state XML if allCompliant bool == true
        if (allCompliant == true)
        {
            if (File.Exists(MainEntry.thirdPartyStateXMLPath))
            {
                XDocument doc = XDocument.Load(MainEntry.thirdPartyStateXMLPath);

                DateTime localCurrentTime = DateTime.Now;
                DateTime utcCurrentTime = DateTime.UtcNow;

                XElement root = new XElement("Compliance_Status");

                root.Add(new XElement("Last_Known_Compliant_UTC", utcCurrentTime));
                root.Add(new XElement("Last_Known_Compliant_LocalTime", localCurrentTime.ToString()));
                doc.Element("Compliance_Items").Add(root);
                doc.Save(MainEntry.thirdPartyStateXMLPath);

            }

        }

That renders the following XML:

<?xml version="1.0" encoding="utf-8"?>
<Compliance_Items>
  <Compliance_Status>
    <Last_Known_Compliant_UTC>2014-04-03T23:22:31.507088Z</Last_Known_Compliant_UTC>
    <Last_Known_Compliant_LocalTime>4/3/2014 4:22:31 PM</Last_Known_Compliant_LocalTime>
  </Compliance_Status>
</Compliance_Items>

This code generates the *Last_Known_Compliant_UTC* and *Last_Known_Compliant_LocalTime* elements and values. On subsequent runs of the code I want it to only replace the values of the existing elements, but as written now the following is re-created each time and keeps stacking in the XML:

<Compliance_Status>
     <Last_Known_Compliant_UTC>2014-04-03T23:22:31.507088Z</Last_Known_Compliant_UTC>
     <Last_Known_Compliant_LocalTime>4/3/2014 4:22:31 PM</Last_Known_Compliant_LocalTime>
</Compliance_Status>

How can I achieve the desired effect?

If you want to get a specific item and modify it you can do the following:

var xmlDocument = XDocument.Load("path");

var element = xmlDocument
.Descendants("Compliance_Status")
.FirstOrDefault(x => (DateTime)x.Element("Last_Known_Compliant_UTC") == someValue)

if(element != null) 
  /* update the value simply using element.Value = something 
     and save the xml file  xmlDocument.Save("path") */

If you want to replace your element with another element you can use XElement.ReplaceWith method.

I have a c# app that writes to XML using the following code:

     //Write last compliant elements to state XML if allCompliant bool == true
        if (allCompliant == true)
        {
            if (File.Exists(MainEntry.thirdPartyStateXMLPath))
            {
                XDocument doc = XDocument.Load(MainEntry.thirdPartyStateXMLPath);

                DateTime localCurrentTime = DateTime.Now;
                DateTime utcCurrentTime = DateTime.UtcNow;

                XElement root = new XElement("Compliance_Status");

                root.Add(new XElement("Last_Known_Compliant_UTC", utcCurrentTime));
                root.Add(new XElement("Last_Known_Compliant_LocalTime", localCurrentTime.ToString()));
                doc.Element("Compliance_Items").Add(root);
                doc.Save(MainEntry.thirdPartyStateXMLPath);

            }

        }

That renders the following XML:

<?xml version="1.0" encoding="utf-8"?>
<Compliance_Items>
  <Compliance_Status>
    <Last_Known_Compliant_UTC>2014-04-03T23:22:31.507088Z</Last_Known_Compliant_UTC>
    <Last_Known_Compliant_LocalTime>4/3/2014 4:22:31 PM</Last_Known_Compliant_LocalTime>
  </Compliance_Status>
</Compliance_Items>

This code generates the *Last_Known_Compliant_UTC* and *Last_Known_Compliant_LocalTime* elements and values. On subsequent runs of the code I want it to only replace the values of the existing elements, but as written now the following is re-created each time and keeps stacking in the XML:

<Compliance_Status>
     <Last_Known_Compliant_UTC>2014-04-03T23:22:31.507088Z</Last_Known_Compliant_UTC>
     <Last_Known_Compliant_LocalTime>4/3/2014 4:22:31 PM</Last_Known_Compliant_LocalTime>
</Compliance_Status>

How can I achieve the desired effect?

If you want to get a specific item and modify it you can do the following:

var xmlDocument = XDocument.Load("path");

var element = xmlDocument
.Descendants("Compliance_Status")
.FirstOrDefault(x => (DateTime)x.Element("Last_Known_Compliant_UTC") == someValue)

if(element != null) 
  /* update the value simply using element.Value = something 
     and save the xml file  xmlDocument.Save("path") */

If you want to replace your element with another element you can use XElement.ReplaceWith method.

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