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C# Dynamic LINQ Contains using an array only evaluates the first value

Relatively new to C# and started using Dynamic LINQ to filter a data table adapter using a string. The issue I'm having is that the Where clause only seems to evaluate the first value in the string and none of the others. Here is the code I am using.
string[] ids = new string[] { "12345", "67891", "45878" };
var resultQ = (from pr in table1 select pr).AsQueryable();
var iq = resultQ.Where("#0.Contains(FieldName)", ids);
It works but only for the first value "12345" so the output of iq displays all fields for "12345". I tried using linq.dynamic.core to see if that would help but the still same result (or I haven't used it properly). I know I'm probably missing something minor here but any help would be greatly appreciated.
Also on a separate note: I wanted to convert the end result of iq which is a IQueryable type to EnumerationRowCollection type. Is this possible?
Thanks in advance

Managed to fix both points now. Either set string[] to string for dynamic LINQ to get all values in list as coded below
string ids = "12345,67891,45878";
var resultQ = (from pr in table1 select pr).AsQueryable();
var iq = resultQ.Where("#0.Contains(FieldName)", ids);
or use Syed's suggestion and change the LINQ query and keep the array (thanks again Seyed)
For the conversion of IQueryable type to EnumerationRowCollection I changed EnumerationRowCollection to IEnumerable and this worked for all my LINQ queries
Thanks

Just use this. It will works fine.
string[] ids = new string[] { "12345", "67891", "45878" };
var resultQ = (from pr in table1 select pr).AsQueryable();
var iq = resultQ.Where(w => ids.Contains(w.Id)).ToList();

How to use a dynamically-created string as a WHERE condition in Linq

I've to create method which returns IQueryable, and tor depends on exact type.
Is it possible to prepare any criteria which could be used after WHERE statement to get that?
for example, if T == License i use "c.fkCustomer == Organization.Customer"
if T== People , I use "c.fkPeople== Organization.People" etc.
XPQuery<T> cQuery = new XPQuery<T>(cSession);
IQueryable CurrQr = from c in cQuery
where "c.fkCustomer == Organization.Customer"
select c;
Can someone suggest something, how to achieve this goal?

I think you would be better off to use a lambda as an argument here rather than dynamic linq eg.
public IQueriable<T> MyQuery<T>(Expression<Func<T, bool>> predicate)
{
return new XPQuery<T>(cSession).Where(predicate)/*and any other bits you want at the moment this is a straight up where clause so kinda pointless*/;
}
then you can call it with:
MyQuery(c=> c.fkCustomer == Organization.Customer)
or
MyQuery(c=> c.fkPeople == Organization.People)

Yes, this can be done. One way to do this is to use the Dynamic Query Library which you can find here along with detailed information on how to use it:
http://weblogs.asp.net/scottgu/archive/2008/01/07/dynamic-linq-part-1-using-the-linq-dynamic-query-library.aspx

Dynamic LINQ querying of an ExpandoObject?

Is there any way to use the LINQ dynamic query library (System.Linq.Dynamic) to evaluate a condition based on the properties of an ExpandoObject? The following code throws an exception on the "var e..." line, saying "No property or field 'Weight' exists in type ExpandoObject":-
const string TestCondition = "MyStateBag.Foo >= 50 && MyStateBag.Bar >= 100";
dynamic myStateBag = new ExpandoObject();
myStateBag.Foo = 70;
myStateBag.Bar = 100;
var p = Expression.Parameter(typeof(ExpandoObject), "MyStateBag");
var e = DynamicExpression.ParseLambda(new[] { p }, null, TestCondition);
var result = e.Compile().DynamicInvoke(myStateBag);
Assert.IsTrue(result);
The alternative would be to implement the "statebag" as a dictionary, but this will result in a slightly more verbose condition string, e.g. MyStateBag["Foo"] >= 50 && MyStateBag["Bar"] >= 100. As this is going to be used as the basis of a user scripting environment, I would prefer the simpler ExpandoObject syntax if it's possible to achieve.

Not directly. The dynamic LINQ library boils down to an expression-tree, and expression trees do not directly support dynamic. Most likely, the dynamic query library is using Expression.PropertyOrField to handle .Foo etc, and that will not work with dynamic.
You could perhaps write a custom expression parser that replaces this with lots of lookup code if it finds the parameter is a dictionary; not fun, though.

MongoDB C# Driver multiple field query

Using the MongoDB C# driver How can I include more than one field in the query (Im using vb.net)
I know how to do (for name1=value1)
Dim qry = Query.EQ("name1","value1")
How can I modify this query so I can make it find all documents where name1=value1 and name2=value2?
( Similar to )
db.collection.find({"name1":"value1","name2":"value2"})

I wanted to search a text in different fields and Full Text Search doesn't work for me even after wasting so much time. so I tried this.
var filter = Builders<Book>.Filter.Or(
Builders<Book>.Filter.Where(p=>p.Title.ToLower().Contains(queryText.ToLower())),
Builders<Book>.Filter.Where(p => p.Publisher.ToLower().Contains(queryText.ToLower())),
Builders<Book>.Filter.Where(p => p.Description.ToLower().Contains(queryText.ToLower()))
);
List<Book> books = Collection.Find(filter).ToList();

You can use:
var arrayFilter = Builders<BsonDocument>.Filter.Eq("student_id", 10000)
& Builders<BsonDocument>.Filter.Eq("scores.type", "quiz");
Reference: https://www.mongodb.com/blog/post/quick-start-csharp-and-mongodb--update-operation

And doesn't always do what you want (as I found was the case when doing a not operation on top of an and). You can also create a new QueryDocument, as shown below. This is exactly the equivalent of what you were looking for.
Query.Not(new QueryDocument {
{ "Results.Instance", instance },
{ "Results.User", user.Email } }))

Storing LINQ queries as variables/constants?

Say I have a LINQ-to-XML query that generates an anonymous type like this:
var aQuery =
(from a in document.Root.Elements("items")
select new {
id = a.Attribute("id").Value,
type = a.Attribute("type").Value,
modified = a.Attribute("modified").Value
});
if there a way to store that query expression in a variable or constant and then execute at runtime? The basic idea is that I have a bunch of these expressions and it would be handy if they could all be defined in one place and then invoked dynamically thru a single method where I just need to pass in the XML document and which expression to use. Thanks.

You could define them as methods quite easily, though you'd forfit the right to use anonymous types.
public static IQueryable<Item> GetItemsFromXml(XDocument document)
{
return (from a in document.Root.Elements("items")
select new Item
{
Id = a.Attribute("id").Value,
Type = a.Attribute("type").Value,
Modified = a.Attribute("modified").Value
});
}
Having said that, patterns like the repository pattern are used to wrap the whole process of accessing data.