asked on

XML Data in to Structure

I have an xml file and want to read the xml in to array of structure, for example

xml file looks like this:-
<MarkupItems>
<items>
</TagValue>
</TagID>
<InputOffset>
</OffsetValue>
</OffsetLength>
</InputOffset>
<OutputOffset>
</OffsetValue>
</OffsetLength>
</OutputOffset>
</items>
<items>
</TagValue>
</TagID>
<InputOffset>
</OffsetValue>
</OffsetLength>
</InputOffset>
<OutputOffset>
</OffsetValue>
</OffsetLength>
</OutputOffset>
</items>
</MarkupItems>

my structure looks like this:-
public struct Offset
{
      public ulong OffsetValue;
      public ulong OffsetLength;
}
public struct TagItem
{
      public Offset InputOffset;
      public Offset OutputOffset;
      public string TagValue;
      public string TagID;
}
public struct MarkUpItems
{
TagItem[] _items;
}

now i want to read the xml file in to the markupitems structure.

ASKER CERTIFIED SOLUTION

Razzie_

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angireddy

ASKER

Hello Mr.Razzie,

its saying Object Reference not set to an instance of an object for the line

inputOffset.OffsetValue = Convert.ToUInt64(itemNodes[i].SelectSingleNode("InputOffset/OffsetValue").InnerText);

Reddy

Razzie_

That is correct. As I stated in my post, there is no error checking for correct input. You'd have to check if the Nodes aren't empty before converting them to a long valuetype. (if ......InnerText != String.Empty) or something, etc :)

angireddy

ASKER

Hi,

how to write back the marupItems back to the xml file using the same example as above.

thanking you
reddy

Razzie_

The correct way to do this would be by rebuilding the XmlDocument. The complete code is a lot of work but below is how it is done. Just fill in the missing data:

---------------------------------------------------------------------------------------------
// Create all the nodes
XmlElement xmlElementRoot = xmlDoc.CreateElement("MarkUpItems");
XmlElement xmlElementItems = xmlDoc.CreateElement("items");
....
XmlElement xmlElementOL = xmlDoc.CreateElement("OffsetLength");

// Create the text for the nodes. Obtain the data from the struct.
XmlText xmlTextOL = xmlDoc.CreateTextNode(tagItem.OutputOffset.OffsetLength);
....
etc

// Append the text elements to the nodes
xmlElementOL .AppendChild(xmlTextOL);
...
etc

// Connect the nodes to eachother. Start with root node, its childeren, THEIR childeren, etc.
xmlDoc.AppendChild(xmlElementRoot);
xmlElementRoot.AppendChild(xmlElementItems);
xmlElementItems.AppendChild(xmlElementOutputOffset);
...
etc

----------------------------------------------------------------------

Use a foreach loop like foreach(TagItem t in markUpItems._items) to get all items nodes.