通过正则表达式删除xsi nil

Question

I have a third party component that produce serialized xml and stored procedure that parse xml and insert values into tables.

I am having trouble with xsi nil handled in the component and sql stored procedure. I don't have control to change either the component or the stored procedure. So the IsNullable attribute on the property solution and not xsi=true on the procedure solution doesn't help me.

I am trying to handle this using regex.

.*xsi\:nil\=\"true\" \/\>

The above regex match works perfect for the below input

<Root xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
<prop1>
    <prop11>abc</prop11>
    <prop12 xsi:nil="true" />
    <prop13>def</prop13>
</prop1>
</Root>

But not for this input

<Root xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema"><prop1><prop11>abc</prop11><prop12 xsi:nil="true" /><prop13>def</prop13></prop1></Root>

Desired output is

<Root xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
<prop1>
    <prop11>abc</prop11>
    <prop13>def</prop13>
</prop1>
</Root>

Update: The property name and the level is only known at run time. Please refer a different xml below

<Root xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
<pa>
    <paa>abc</paa>
    <pab xsi:nil="true" />
    <pac>def</pac>
            <pad>
               <pada>val1</pada>
               <padb xsi:nil="true" />
               <padc>
                     <padca>vala</padca>
                     <padcb xsi:nil="true" />
               </padc>
            <pad>
</prop1>
</Root>

The desired output for the above xml is

<Root xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
<pa>
    <paa>abc</paa>
    <pac>def</pac>
            <pad>
               <pada>val1</pada>
               <padc>
                     <padca>vala</padca>
               </padc>
            <pad>
</prop1>
</Root>

Could someone please help me

Thanks,

Esen

Answer 1

Using the XPath from this library: https://github.com/ChuckSavage/XmlLib/

I get the XElements that have xsi:nil=true with:

XElement root = XElement.Load(file);
// or root = XElement.Parse(xml);
IEnumerable<XElement> result = root.XPath("//*[@xsi:nil={0}]", true);
result.ToList().ForEach(x => x.Remove());
root.Save(file);
// or xml = root.ToString();

I tested it with this XML:

<Root xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
  <prop1>
    <prop10 xsi:nil="true" />
    <prop11>abc</prop11>
    <prop12 xsi:nil="true" />
    <prop13>def</prop13>
    <prop14 xsi:nil="true" />
    <prop15>def</prop15>
    <prop16 xsi:nil="true" />
  </prop1>
</Root>

And found all 4 XElements. From there they are removed.

The resulting XML is:

<Root xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
  <prop1>
    <prop11>abc</prop11>
    <prop13>def</prop13>
    <prop15>def</prop15>
  </prop1>
</Root>

If you don't care that the xsi:nil is true, and you just want all nodes with the xsi:nil attribute removed, you can frame the XPath like:

IEnumerable<XElement> result = root.XPath("//*[@xsi:nil]");

Answer 2

Using Linq to XML

using System.Xml.Linq;

        var f = XDocument.Load("c:\\01.xml");
        var xsi = XNamespace.Get("http://www.w3.org/2001/XMLSchema-instance");
        var nills = from n in f.Root.Elements("prop1").Elements()
                    where n.Attribute(xsi + "nil") != null
                    select n;

        nills.ToList().ForEach(x => x.RemoveAttributes());

        f.Save("c:\\011.xml");

This produced the following result:

<?xml version="1.0" encoding="utf-8"?>
<Root xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
  <prop1>
    <prop11>abc</prop11>
    <prop12 />
    <prop13>def</prop13>
  </prop1>
</Root>