Class StringExtensions

Namespace

Cuemon.Extensions.Xml

Assembly

Cuemon.Extensions.Xml.dll

Extension methods for the string class.

public static class StringExtensions

Inheritance

object

StringExtensions

Examples

StringExtensions in the Xml namespace provides XML escaping, unescaping, element name sanitization, and control-character removal for text content. This example starts with "Use & < > \" ' in XML" and calls EscapeXml to produce "Use & < > " ' in XML", then round-trips back with UnescapeXml. It also demonstrates SanitizeXmlElementName on "1st Element Name!" to replace leading digits and punctuation with underscores, and SanitizeXmlElementText to remove control characters except \t, \n, \r, with optional CDATA section protection that removes "]]>" sequences. Console output displays each transformation result.

using System;
using Cuemon.Extensions.Xml;

namespace MyApp.Xml
{
    public class StringExtensionsExample
    {
        public void Demonstrate()
        {
            // Escape XML special characters
            var unsafeText = "Use & < > \" ' in XML";
            var escaped = unsafeText.EscapeXml();
            Console.WriteLine(escaped); // "Use &amp; &lt; &gt; &quot; &apos; in XML"

            // Unescape XML back to original text
            var unescaped = escaped.UnescapeXml();
            Console.WriteLine(unescaped); // "Use & < > \" ' in XML"

            // Sanitize a string for use as an XML element name
            var invalidName = "1st Element Name!";
            var sanitizedName = invalidName.SanitizeXmlElementName();
            Console.WriteLine(sanitizedName); // "_st_Element_Name_"

            // Sanitize XML element text (remove control characters except \t, \n, \r)
            var invalidText = "Valid text \x00 with \x01 control chars";
            var sanitizedText = invalidText.SanitizeXmlElementText();
            Console.WriteLine(sanitizedText); // "Valid text  with  control chars"

            // Sanitize XML element text with CDATA section rules (discourages "]]>" sequence)
            var cdataText = "text with ]]> inside";
            var sanitizedCdata = cdataText.SanitizeXmlElementText(cdataSection: true);
            Console.WriteLine(sanitizedCdata); // "text with ]] inside"

}}
}

Methods

EscapeXml(string)

Escapes the given XML value.

public static string EscapeXml(this string value)

Parameters

value string

The string to extend.

Returns

string

The input value with an escaped equivalent.

Exceptions

ArgumentNullException

value cannot be null.

SanitizeXmlElementName(string)

Sanitizes the value for any invalid characters.

public static string SanitizeXmlElementName(this string value)

Parameters

value string

The string to extend.

Returns

string

A sanitized string of value.

Remarks

Sanitation rules are as follows:
1. Names can contain letters, numbers, and these 4 characters: _ | : | . | -
2. Names cannot start with a number or punctuation character
3. Names cannot contain spaces

Exceptions

ArgumentNullException

value cannot be null.

SanitizeXmlElementText(string, bool)

Sanitizes the value for any invalid characters.

public static string SanitizeXmlElementText(this string value, bool cdataSection = false)

Parameters

value string

The string to extend.

cdataSection bool

if set to true supplemental CDATA-section rules is applied to value.

Returns

string

A sanitized string of value.

Remarks

Sanitation rules are as follows:
1. The value cannot contain characters less or equal to a Unicode value of U+0019 (except U+0009, U+0010, U+0013)
2. The value cannot contain the string "]]<" if cdataSection is true.

UnescapeXml(string)

Unescapes the given XML value.

public static string UnescapeXml(this string value)

Parameters

value string

The string to extend.

Returns

string

The input value with an unescaped equivalent.

Exceptions

ArgumentNullException

value cannot be null.