private static int ComputeSum(ParameterInfo[] parameters, Type[] argTypes)
{
Debug.Assert(parameters.Length == argTypes.Length);
var sum = 0;
for (var i = 0; i <= parameters.Length - 1; i++)
{
sum += ImplicitConverter.GetImplicitConvertScore(argTypes[i], parameters[i].ParameterType);
}
return(sum);
}
private static bool AreValidArgumentsForParameters(Type[] argTypes, ParameterInfo[] parameters)
{
Debug.Assert(argTypes.Length == parameters.Length);
// Match if every given argument is implicitly convertible to the method's corresponding parameter
for (var i = 0; i <= argTypes.Length - 1; i++)
{
if (ImplicitConverter.EmitImplicitConvert(argTypes[i], parameters[i].ParameterType, null) == false)
{
return(false);
}
}
return(true);
}
public override MethodBase SelectMethod(BindingFlags bindingAttr, MethodBase[] match, Type[] types, ParameterModifier[] modifiers)
{
foreach (var methodBase in match)
{
var parameters = methodBase.GetParameters();
var leftValid = ImplicitConverter.EmitImplicitConvert(leftType, parameters[0].ParameterType, null);
var rightValid = ImplicitConverter.EmitImplicitConvert(rightType, parameters[1].ParameterType, null);
if (leftValid & rightValid)
{
return(methodBase);
}
}
return(null);
}
private bool IsParamArrayMatch(Type[] argTypes, ParameterInfo[] parameters, ParameterInfo paramArrayParameter)
{
// Get the count of arguments before the paramArray parameter
var fixedParameterCount = paramArrayParameter.Position;
var fixedArgTypes = new Type[fixedParameterCount];
var fixedParameters = new ParameterInfo[fixedParameterCount];
// Get the argument types and parameters before the paramArray
Array.Copy(argTypes, fixedArgTypes, fixedParameterCount);
Array.Copy(parameters, fixedParameters, fixedParameterCount);
// If the fixed arguments don't match, we are not a match
if (AreValidArgumentsForParameters(fixedArgTypes, fixedParameters) == false)
{
return(false);
}
// Get the type of the paramArray
ParamArrayElementType = paramArrayParameter.ParameterType.GetElementType();
// Get the types of the arguments passed to the paramArray
var paramArrayArgTypes = new Type[argTypes.Length - fixedParameterCount];
Array.Copy(argTypes, fixedParameterCount, paramArrayArgTypes, 0, paramArrayArgTypes.Length);
// Check each argument
foreach (var argType in paramArrayArgTypes)
{
if (ImplicitConverter.EmitImplicitConvert(argType, ParamArrayElementType, null) == false)
{
return(false);
}
}
FixedArgTypes = fixedArgTypes;
ParamArrayArgTypes = paramArrayArgTypes;
// They all match, so we are a match
return(true);
}
private float ComputeScoreForParamArray(ParameterInfo[] parameters, Type[] argTypes)
{
var paramArrayParameter = parameters[parameters.Length - 1];
var fixedParameterCount = paramArrayParameter.Position;
var fixedParameters = new ParameterInfo[fixedParameterCount];
Array.Copy(parameters, fixedParameters, fixedParameterCount);
var fixedSum = ComputeSum(fixedParameters, FixedArgTypes);
var paramArrayElementType = paramArrayParameter.ParameterType.GetElementType();
var paramArraySum = 0;
foreach (var argType in ParamArrayArgTypes)
{
paramArraySum += ImplicitConverter.GetImplicitConvertScore(argType, paramArrayElementType);
}
var score = argTypes.Length > 0 ? (fixedSum + paramArraySum) / argTypes.Length : (float)0;
// The param array score gets a slight penalty so that it scores worse than direct matches
return(score + 1);
}