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How can I insert an item into a List<T> without bumping the item at that index to the back?

I'm trying to Insert an item at the start of a list using foo.Insert(0, bar); but it seems that the item that was at index 0 before is getting bumped to the back of the list instead of moving to index 1. I've tried creating a new List and adding the values in order, but it looks messy/hacky.
Is there any clean way of doing this? If so, how?
Thank you.

As already said in comments, insert into List<T> preserve ordering, so described behaviour shouldn't happen.
Simple example:
var lst = new List<int> {1,2,3,4};
lst.Insert(0,0);
lst.Dump();

Add a range of items to the beginning of a list?

The method List<T>.AddRange(IEnumerable<T>) adds a collection of items to the end of the list:
myList.AddRange(moreItems); // Adds moreItems to the end of myList
What is the best way to add a collection of items (as some IEnumerable<T>) to the beginning of the list?

Use InsertRange method:
myList.InsertRange(0, moreItems);

Use InsertRange method:
List<T>.InsertRange(0, yourcollection);
Also look at Insert method which you can add an element in your list with specific index.
Inserts an element into the List at the specified index.
List<T>.Insert(0, T);

List<String> listA=new List<String>{"A","B","C"};
List<String> listB=new List<String>{"p","Q","R"};
listA.InsertRange(0, listB);
Here suppose we have 2 list of string... then using the InsertRange method we can pass the starting index where we want to insert/push the new range(listB) to the existing range(listA)
Hope this clears the code.

Please try List<T>.InsertRange(0, IEnumerable<T>)

get fixed number of items from array list c#

I would like to create a list variable of items from another list. So lets say I have a list of 100 items I would like to pull items 25 - 35 and put them inside of another list. is there a way of doing this without calling a big for statement and pulling out the element one by one and putting that into a list.

you can use .Skip and .Take from System.Linq ....
Like this:
var result = myList.Skip(24).Take(10);
and if you need use ToList on the result to get another list

For a List<T>, you can use the GetRange Method.
Creates a shallow copy of a range of elements in the source List(Of
T).
Do note that the second argument represents the count of elements in the range, not the end-index of the range.
Since you mention ArrayList, I should point out that while it too has a GetRange, method, the type is considered essentially legacy since .NET 2.0.

Use both Take and Skip
var newList = oldList.Skip(25).Take(10);

Shortest way to bind a certain amout of items from a list to a data source?

Anyone know how to select a certain amount of items in a List to bind to a DataSource? Basically I'm getting back 10 items (which I don't have control over) and I only need to show 5. Originally I was thinking of using a loop and adding 5 items to a new list but that seems like a lot of code. Is there an expression that I can use to select the first 5?
//Returns a List<DataItem>
MyDataListControl.DataSource = Helper.GetDataItems(); //<= Possible expression?

You may take a look at the Skip and Take LINQ extension methods. So in your case if you wanted to take only the first 5 elements of some IEnumerable<T>:
MyDataListControl.DataSource = Helper.GetDataItems().Take(5).ToList();

What about List's GetRange method? Have you tried that? I don't the internal workings of the method; whether it also creates a new list or not.
GetRange(int index, int count)
Here is the msdn link for it.

RemoveRange will probably be best as you won't have to instanciate a new list, unless that happens internally anyway.. Just make sure you're always getting 10 items or you'll potentially get an ArgumentOutOfRangeException.
list.RemoveRange(5, 5);
That should leave you with the first five items.

Removing a list of objects from another list

I've been looking for something like that for days. I'm trying to remove all the elements from a bigger list A according to a list B.
Suppose that I got a general list with 100 elements with differents IDS and I get another list with specific elements with just 10 records. I need remove all the elements from the first list that doesn't exists inside the second list.
I'll try to show the code that I actually don't know how it didnt works.
List<Obj> listA = new List<Obj>();
List<Obj> listB = new List<Obj>();
//here I load my first list with many elements
//here I load my second list with some specific elements
listA.RemoveAll(x => !listB.Contains(x));
I don't know why but it's not working. If I try this example with a List<int> type, it works nicely but I'd like to do that with my object. This object got an ID but I don't know how to use this ID inside the LINQ sentence.

You need to compare the IDs:
listA.RemoveAll(x => !listB.Any(y => y.ID == x.ID));
List(T).RemoveAll

I believe you can use the Except Extension to do this.
var result = listA.Except(listB)
Reference: http://www.dotnetperls.com/except

If you want to remove a list of objects (listB) from another list (listA) use:
listA = listA.Except(listB).ToList()
Remember to use ToList() to convert IEnumerable<Obj> to List<Obj>.

who ever is viewing this now.I think var result = listA.Intersect(listB) will give the result for common values in the both the list.

According to the documentation on MSDN ( http://msdn.microsoft.com/en-us/library/bhkz42b3.aspx ), contains uses the default Equality comparer to determine equality, so you could use IEquatable's Equals method on your Obj class to make it work. HiperiX mentions the ref comparison above.
How to add the IEquateable interface: http://msdn.microsoft.com/en-us/library/ms131190.aspx