ReaderUtils.cs

/*
* NanoXLSX is a small .NET library to generate and read XLSX (Microsoft Excel 2007 or newer) files in an easy and native way
* Copyright Raphael Stoeckli © 2025
* This library is licensed under the MIT License.
* You find a copy of the license in project folder or on: http://opensource.org/licenses/MIT
*/
 
using System;
using System.Linq;
using System.Xml;
 
namespace NanoXLSX.Internal
{
    public static class ReaderUtils
    {
        public static string GetAttribute(XmlNode node, string targetName, string fallbackValue = null)
        {
            if (node.Attributes == null || node.Attributes.Count == 0)
            {
                return fallbackValue;
            }
 
            foreach (XmlAttribute attribute in node.Attributes)
            {
                if (attribute.Name == targetName)
                {
                    return attribute.Value;
                }
            }
 
            return fallbackValue;
        }

        public static bool GetAttributeOfChild(XmlNode node, string childNodeName, string attributeName, out string output)
        {
            XmlNode childNode = GetChildNode(node, childNodeName);
            if (childNode != null)
            {
                output = GetAttribute(childNode, attributeName);
                return true;
            }
            output = null;
            return false;
        }

        public static XmlNode GetChildNode(XmlNode node, string name)
        {
            if (node != null && node.HasChildNodes)
            {
                return node.ChildNodes.Cast<XmlNode>().FirstOrDefault(c => c.LocalName.Equals(name, StringComparison.OrdinalIgnoreCase));
            }
            return null;
        }

        internal static bool IsNode(XmlNode node, string name)
        {
            return node.LocalName.Equals(name, StringComparison.OrdinalIgnoreCase);
        }

        internal static string DiscoverPrefix(XmlDocument document, string targetName)
        {
            foreach (XmlNode node in document.ChildNodes)
            {
                if (node.LocalName == targetName)
                {
                    return node.Prefix;
                }
            }
            return "";
        }

        internal static XmlNodeList GetElementsByTagName(XmlDocument document, string tagName, string prefix)
        {
            if (string.IsNullOrEmpty(prefix))
            {
                return document.GetElementsByTagName(tagName);
            }
            else
            {
                return document.GetElementsByTagName(prefix + ":" + tagName);
            }
        }
 
    }
}