在List中转换IEnumerable <T>

Question

I am creating a control that receive in datasource a DataSet or List

How i convert a IEnumerable to List in a CreateChildControls event?

protected override int CreateChildControls(IEnumerable dataSource, bool dataBinding)
{
    if (dataSource is System.Data.DataSet)
    {
    }
    else if(dataSource is IList)
    {
    }
}

Answer 1

Usually one would use the IEnumerable<T>.ToList() extensionmethod from Linq but in your case you can not use it (right away) because you have the non-generic IEnumerable interface. Sou you will have to cast it first (also using Linq):

datasource.Cast<object>().ToList();

No matter what you original collection actually ist, this will always succeed.

Answer 2

I re-read your question and it seems that you are receiving a dataset which is ALREADY a list OR a DataSet, but it is cast to an IEnumerable. In this case, simply do

IList myList = (IList)datasource //will throw exception if invalid

or

IList myList = datasource as IList //mylist will be null if conversion cannot be made

Answer 3

To answer your question 'how i can get the original Type and not set a object type?'.

Every type in .NET framework contains GetType method to fetch the type of the specified object. You can use it before ToList method.