/// <summary>Determines if the <paramref name="expr"/> is a call to ThenBy.</summary>
/// <param name="expr">Expression to inspect.</param>
/// <returns>Instance of the <see cref="OrderByCallMatch"/> class if the <paramref name="expr"/> is a ThenBy call,
/// or null otherwise.</returns>
internal static OrderByCallMatch MatchThenByCall(Expression expr)
{
if (expr.NodeType == ExpressionType.Call && TypeSystem.IsMethodLinqThenBy(((MethodCallExpression)expr).Method))
{
MethodCallExpression call = (MethodCallExpression)expr;
LambdaExpression lambda = (LambdaExpression)ExpressionUtil.RemoveQuotes(call.Arguments[1]);
Expression body = ExpressionUtil.RemoveQuotes(lambda.Body);
return(new OrderByCallMatch
{
MethodCall = call,
Source = call.Arguments[0],
Lambda = lambda,
LambdaBody = body
});
}
else
{
return(null);
}
}
/// <summary>Visits method call expression.</summary>
/// <param name="m">The method call expression.</param>
/// <returns>The visited expression.</returns>
internal override Expression VisitMethodCall(MethodCallExpression m)
{
if (m.Method.Name == "Where")
{
Expression source = this.Visit(m.Arguments[0]);
Expression lambdaArg = this.Visit(m.Arguments[1]);
LambdaExpression lambda = (LambdaExpression)ExpressionUtil.RemoveQuotes(lambdaArg);
Expression body = ExpressionUtil.RemoveQuotes(lambda.Body);
Expression newBody;
newBody = this.SimplifyBoolComparison(body);
if (newBody != null)
{
return(Expression.Call(
m.Method,
source,
Expression.Lambda(newBody, lambda.Parameters.ToArray())));
}
}
return(base.VisitMethodCall(m));
}