private static Expression GetCallExpression(
MethodInfo methodInfo,
ParameterExpression instanceParameter,
Type instanceType,
Type returnType,
IEnumerable <ParameterInfo> parameterInfos,
IEnumerable <Expression> parameterExpressions)
{
if (methodInfo == null)
{
throw new ArgumentNullException("methodInfo");
}
returnType = returnType ?? typeof(void);
parameterInfos = parameterInfos ?? Enumerable.Empty <ParameterInfo>();
parameterExpressions = parameterExpressions ?? Enumerable.Empty <ParameterExpression>();
var coercedParameters = parameterExpressions.Zip(
parameterInfos,
(parameterExpression, parameterInfo) =>
parameterExpression.Coerce(parameterExpression.Type, parameterInfo.ParameterType));
MethodCallExpression call;
if (methodInfo.IsStatic)
{
call = Expression.Call(methodInfo, coercedParameters);
}
else
{
if (instanceParameter == null)
{
throw new ArgumentNullException("instanceParameter", "'instanceParameter' cannot be null when 'methodInfo' is not static.");
}
if (instanceType == null)
{
throw new ArgumentNullException("instanceType", "'instanceType' cannot be null when 'methodInfo' is not static.");
}
var instanceCast = instanceParameter.Coerce(instanceType, methodInfo.DeclaringType);
call = Expression.Call(instanceCast, methodInfo, coercedParameters);
}
var callCast = call.Coerce(methodInfo.ReturnType, returnType);
return(callCast);
}
private static MemberExpression GetField(FieldInfo fieldInfo, Type declaringType, ParameterExpression instanceParameter)
{
MemberExpression field;
if (fieldInfo.IsStatic)
{
field = Expression.Field(null, fieldInfo);
}
else
{
var instanceCast = instanceParameter.Coerce(declaringType, fieldInfo.DeclaringType);
field = Expression.Field(instanceCast, fieldInfo);
}
return(field);
}
private static Expression GetNonGenericCallExpression(
MethodInfo methodInfo,
ParameterExpression instanceParameter,
IEnumerable <ParameterInfo> parameterInfos,
ParameterExpression parameter)
{
if (methodInfo == null)
{
throw new ArgumentNullException("methodInfo");
}
parameterInfos = parameterInfos ?? Enumerable.Empty <ParameterInfo>();
var coercedParameters =
parameterInfos.Select(
(parameterInfo, i) =>
Expression.ArrayAccess(parameter, Expression.Constant(i)).Coerce(typeof(object), parameterInfo.ParameterType));
MethodCallExpression call;
if (methodInfo.IsStatic)
{
call = Expression.Call(methodInfo, coercedParameters);
}
else
{
if (instanceParameter == null)
{
throw new ArgumentNullException("instanceParameter", "'instanceParameter' cannot be null when 'methodInfo' is not static.");
}
var instanceCast = instanceParameter.Coerce(typeof(object), methodInfo.DeclaringType);
call = Expression.Call(instanceCast, methodInfo, coercedParameters);
}
var callCast = call.Coerce(methodInfo.ReturnType, typeof(object));
return(callCast);
}