Question

I’m building an XML Deserializer for a project and I run across this type of code situation fairly often:

var myVariable = ParseNDecimal(xml.Element('myElement')) == null ?                   0 : ParseNDecimal(xml.Element('myElement')).Value; 

Is there a better way to write this statement?

EDIT : Perhaps I should have clarified my example as I do have a helper method to parse the string into a decimal.

Answer 1

You can use extension method:

public static T TryGetValue<T>( this XmlElement element ) {     if ( null == element ) return default(T);     return (T)element.Value; } ... ... var myVariable = xml.Element('myElement').TryGetValue<decimal>(); 

EDIT:

The ‘universal’ solution:

static class Program {     static void Main() {         var xmlDecimal = new XElement( 'decimal' );         xmlDecimal.Value = ( 123.456m ).ToString();         decimal valueOfDecimal_1 = xmlDecimal.ValueAs<decimal>( decimal.TryParse );         bool valueOfBool_1 = xmlDecimal.ValueAs<bool>( bool.TryParse );          var xmlBool = new XElement( 'bool' );         xmlBool.Value = true.ToString();         decimal valueOfDecimal_2 = xmlBool.ValueAs<decimal>( decimal.TryParse );         bool valueOfBool_2 = xmlBool.ValueAs<bool>( bool.TryParse );     } }  public static class StaticClass {     public delegate bool TryParseDelegate<T>( string text, out T value );     public static T ValueAs<T>( this XElement element, TryParseDelegate<T> parseDelegate ) {         return ValueAs<T>( element, parseDelegate, default( T ) );     }     public static T ValueAs<T>( this XElement element, TryParseDelegate<T> parseDelegate, T defaultValue ) {         if ( null == element ) { return defaultValue; }          T result;         bool ok = parseDelegate( element.Value, out result );         if ( ok ) { return result; }          return defaultValue;     } }