public static Expression BuildConversionCall(this IExpressionGenerator gen, MethodInfo method, Expression input, Type resultType) {
Contract.Requires(gen != null);
Contract.Requires(method != null);
Contract.Requires(input != null);
var methodParams = method.GetParameters();
if (methodParams.Length > 0) {
Contract.Assume(methodParams[0] != null);
var paramType = methodParams[0].ParameterType;
if (input.Type != paramType) {
input = gen.GenerateConversionOrThrow(paramType, input);
}
}
Expression result = method.BuildCallExpression(input);
if (resultType != null && result.Type != resultType) {
result = gen.GenerateConversionOrThrow(resultType, result);
}
return result;
}
public static Expression BuildConversionCall(this IExpressionGenerator gen, MethodInfo method, Type resultType, params Expression[] inputExpressions) {
Contract.Requires(gen != null);
Contract.Requires(method != null);
Contract.Requires(inputExpressions != null);
Contract.Requires(Contract.ForAll(inputExpressions, x => x != null));
var methodParams = method.GetParameters();
if(methodParams.Length != inputExpressions.Length)
throw new ArgumentException(String.Format("{0} input expressions are required.", methodParams.Length));
for (int i = 0; i < methodParams.Length; i++) {
Contract.Assume(methodParams[i] != null);
var paramType = methodParams[i].ParameterType;
var inputExpression = inputExpressions[i];
if (inputExpression.Type != paramType) {
inputExpressions[i] = gen.GenerateConversionOrThrow(paramType, inputExpression);
}
}
Expression result = method.BuildCallExpression(inputExpressions);
if (resultType != null && result.Type != resultType)
result = gen.GenerateConversionOrThrow(resultType, result);
return result;
}
