public void LambdaExpression()
{
var tparameter = ODataExpression.Parameter("t");
var cparameter = ODataExpression.Parameter("c");
var l1 = new ODataLambdaExpression
{
Body = ODataExpression.PropertyOrField("Items", cparameter),
Parameters = new[] { cparameter }
};
var aparameter = ODataExpression.Parameter("a");
var bparameter = ODataExpression.Parameter("b");
var l2 = new ODataLambdaExpression
{
Body = ODataExpression.Add(ODataExpression.PropertyOrField("Id", aparameter), ODataExpression.PropertyOrField("Id", bparameter)),
Parameters = new[] { aparameter, bparameter }
};
var method = new ODataMethodCallExpression
{
Context = ODataExpression.PropertyOrField("Customers", tparameter),
MethodName = "SelectMany",
Arguments = new ODataExpression[]
{
l1, l2
}
};
var expression = new ODataLambdaExpression
{
Body = method,
Parameters = new [] { tparameter }
};
//t => t.Customers.SelectMany(c => c.Customers, (a, b) => (a.Id + b.Id))
//t => t.Customers.SelectMany(c => c.Customers, (a, b) => (a.Id + b.Id))
var methods =
typeof(Queryable).GetMethods()
.Where(x => x.Name == "SelectMany" && x.GetParameters().Length == 3)
.ToArray();
foreach (var methodInfo in methods)
{
// var arguments = methodInfo.GetGenericArguments();
// var parameter = DynamicExpression.Parameter(arguments[0], "t");
// var dd = DynamicExpression.Property(parameter, "Customers");
//
}
//var expr = Linq.Linq.Expr<Customer, IEnumerable<int>>(t => t.Customers.SelectMany(c => c.Items, (a, b) => a.Id + b.Id));
//var translator = new QueryTranslator();
//var d = translator.Invoke<Customer, IEnumerable<int>>(expression);
}