static bool TryParseHexColor(string text, out FastColour result)
{
result = FastColour.White;
byte red, green, blue;
if (!(text.Length == 6 || text.Length == 7))
{
return(false);
}
int offset = text[0] == '#' ? 1 : 0;
if (!TryParseByteHex(text, offset, out red) ||
!TryParseByteHex(text, offset + 2, out green) ||
!TryParseByteHex(text, offset + 4, out blue))
{
return(false);
}
result = new FastColour(red, green, blue, 255);
return(true);
}
/// <summary> Attempts to parse the value of the given configuration key as the specified type. </summary>
/// <param name="configKey"> The key of the configuration option. </param>
/// <param name="defaultValue"> The default value to assign if parsing fails. </param>
/// <param name="value"> The configuration value assigned by the method. </param>
/// <returns> true on success, false on failure. The method can fail if the key is null,
/// the key is not found, or if the value could not be parsed. </returns>
/// <remarks> T can be one of the following types: bool, char, sbyte, short, int, long, byte,
/// ushort, uint, ulong, float, double, decimal, DateTime, Enum. </remarks>
public bool TryParseValueOrDefault <T>(string configKey, T defaultValue, out T value) where T : struct, IConvertible
{
if (configKey == null)
{
value = defaultValue;
return(false);
}
else
{
Type type = typeof(T);
bool parsingWorked = false;
string rawValue;
if (!config.TryGetValue(configKey, out rawValue))
{
value = defaultValue;
Console.WriteLine("Couldn't find key {0} in config. Setting to default value of {1}.", configKey, defaultValue);
return(false);
}
// Switch case doesn't work, and we can't do straight casts in an out parameter.
// Ugly if else chain it is.
if (type == typeof(bool))
{
bool result;
parsingWorked = Boolean.TryParse(rawValue, out result);
value = (T)(ValueType)result;
}
else if (type == typeof(char))
{
char result;
parsingWorked = Char.TryParse(rawValue, out result);
value = (T)(ValueType)result;
}
else if (type == typeof(sbyte))
{
sbyte result;
parsingWorked = SByte.TryParse(rawValue, out result);
value = (T)(ValueType)result;
}
else if (type == typeof(short))
{
short result;
parsingWorked = Int16.TryParse(rawValue, out result);
value = (T)(ValueType)result;
}
else if (type == typeof(int))
{
int result;
parsingWorked = Int32.TryParse(rawValue, out result);
value = (T)(ValueType)result;
}
else if (type == typeof(long))
{
long result;
parsingWorked = Int64.TryParse(rawValue, out result);
value = (T)(ValueType)result;
}
else if (type == typeof(byte))
{
byte result;
parsingWorked = Byte.TryParse(rawValue, out result);
value = (T)(ValueType)result;
}
else if (type == typeof(ushort))
{
ushort result;
parsingWorked = UInt16.TryParse(rawValue, out result);
value = (T)(ValueType)result;
}
else if (type == typeof(uint))
{
uint result;
parsingWorked = UInt32.TryParse(rawValue, out result);
value = (T)(ValueType)result;
}
else if (type == typeof(ulong))
{
ulong result;
parsingWorked = UInt64.TryParse(rawValue, out result);
value = (T)(ValueType)result;
}
else if (type == typeof(float))
{
float result;
parsingWorked = Single.TryParse(rawValue, out result);
value = (T)(ValueType)result;
}
else if (type == typeof(double))
{
double result;
parsingWorked = Double.TryParse(rawValue, out result);
value = (T)(ValueType)result;
}
else if (type == typeof(decimal))
{
decimal result;
parsingWorked = Decimal.TryParse(rawValue, out result);
value = (T)(ValueType)result;
}
else if (type == typeof(DateTime))
{
DateTime result;
parsingWorked = DateTime.TryParse(rawValue, out result);
value = (T)(ValueType)result;
}
else if (type == typeof(FastColour))
{
FastColour result;
parsingWorked = FastColour.TryParse(rawValue, out result);
value = (T)(ValueType)result;
}
else if (type.IsEnum)
{
try {
value = (T)(ValueType)Enum.Parse(type, rawValue, true); // Case insensitive.
parsingWorked = true;
} catch (ArgumentException) {
value = defaultValue; // Stops compilation errors.
parsingWorked = false;
}
}
else
{
value = defaultValue;
throw new InvalidCastException("Cannot parse type " + type.Name);
}
if (!parsingWorked)
{
Console.WriteLine("Couldn't parse value for {0} from config. Setting to default value of {1}.", configKey, defaultValue);
value = defaultValue;
}
return(parsingWorked);
}
}
