There is one other way to achieve this result that is a lot cleaner in usage but requires more code. My implementing a custom type and type converter the following code is possible:
List<int> array = Settings.Default.Testing;
array.Add(new Random().Next(10000));
Settings.Default.Testing = array;
Settings.Default.Save();
To achieve this you need a type with a type converter that allows conversion to and from strings. You do this by decorating the type with the TypeConverterAttribute:
[TypeConverter(typeof(MyNumberArrayConverter))]
public class MyNumberArray ...
Then implementing this type converter as a derivation of TypeConverter:
class MyNumberArrayConverter : TypeConverter
{
public override bool CanConvertTo(ITypeDescriptorContext ctx, Type type)
{ return (type == typeof(string)); }
public override bool CanConvertFrom(ITypeDescriptorContext ctx, Type type)
{ return (type == typeof(string)); }
public override object ConvertTo(ITypeDescriptorContext ctx, CultureInfo ci, object value, Type type)
{
MyNumberArray arr = value as MyNumberArray;
StringBuilder sb = new StringBuilder();
foreach (int i in arr)
sb.Append(i).Append(',');
return sb.ToString(0, Math.Max(0, sb.Length - 1));
}
public override object ConvertFrom(ITypeDescriptorContext ctx, CultureInfo ci, object data)
{
List<int> arr = new List<int>();
if (data != null)
{
foreach (string txt in data.ToString().Split(','))
arr.Add(int.Parse(txt));
}
return new MyNumberArray(arr);
}
}
By providing some convenience methods on the MyNumberArray class we can then safely assign to and from List, the complete class would look something like:
[TypeConverter(typeof(MyNumberArrayConverter))]
public class MyNumberArray : IEnumerable<int>
{
List<int> _values;
public MyNumberArray() { _values = new List<int>(); }
public MyNumberArray(IEnumerable<int> values) { _values = new List<int>(values); }
public static implicit operator List<int>(MyNumberArray arr)
{ return new List<int>(arr._values); }
public static implicit operator MyNumberArray(List<int> values)
{ return new MyNumberArray(values); }
public IEnumerator<int> GetEnumerator()
{ return _values.GetEnumerator(); }
IEnumerator IEnumerable.GetEnumerator()
{ return ((IEnumerable)_values).GetEnumerator(); }
}
Lastly, to use this in the settings you add the above classes to an assembly and compile. In your Settings.settings editor you simply click the "Browse" option and select the MyNumberArray class and off you go.
Again this is a lot more code; however, it can be applied to much more complicated types of data than a simple array.
