<p>I have a method that takes an IQueryable. Is there a LINQ query that will give me back the size of each column in the IQueryable?</p>

<p>To be more clear: this is Linq-to-objects.  I want to get the length of the ToString() of each "column".</p>

It depends.  If you mean is there a completely generic way to make this determination the answer is no.  All IQueryable will give access to is the Type of each expression.  There is no way to arbitrarily map a Type to a column size.
If on the other hand you have the ability to map a Type to members and member type to a column size then yes there is a way to get the size.
```
```
public IEnumerable GetColumnSize(IQueryable source)
{
  var types = MapTypeToMembers(source).Select(x => x.Type);
  return types.Select(x => MapTypeToSize(x));
}
```
```