Why is it not possible to evaluate lambdas in the immediate window?

Question

Is there any particular reason? Is it not possible at all or is it just not implemented yet? Maybe there are any third-party addins that allow lambda evaluations?

Answer 1

If you still need to use Visual Studio 2013, you can actually write a loop, or lambda expression in the immediate window using also the package manager console window. In my case, I added a list at the top of the function:

    private void RemoveRoleHierarchy()
    {
#if DEBUG
        var departments = _unitOfWork.DepartmentRepository.GetAll().ToList();
        var roleHierarchies = _unitOfWork.RoleHierarchyRepository.GetAll().ToList();
#endif

        try
        {
            //RoleHierarchy
            foreach (SchoolBo.RoleHierarchy item in _listSoRoleHierarchy.Where(r => r.BusinessKeyMatched == false))
                _unitOfWork.RoleHierarchyRepository.Remove(item.Id);

            _unitOfWork.Save();
        }
        catch (Exception e)
        {
            Debug.WriteLine(e.ToString());
            throw;
        }
    }

Where my GetAll() function is:

    private DbSet _dbSet;

    public virtual IList GetAll()
    {
        List list;
        IQueryable dbQuery = _dbSet;
        list = dbQuery
            .ToList();

        return list;
    }

Here I kept getting the following error, so I wanted to print out all the items in the various repositories:

InnerException  {"The DELETE statement conflicted with the REFERENCE constraint \"FK_dbo.Department_dbo.RoleHierarchy_OranizationalRoleId\". The conflict occurred in database \"CC_Portal_SchoolObjectModel\", table \"dbo.Department\", column 'OranizationalRoleId'.\r\nThe statement has been terminated."} System.Exception {System.Data.SqlClient.SqlException}

Then, I find out how many records are in the department repository by executing this in the immediate window:

_unitOfWork.DepartmentRepository.GetAll().ToList().Count

Which returned 243.

So, if you execute the following in the package manager console, it prints out all the items:

PM> for($i = 0; $i -lt 243; $i++) { $a = $dte.Debugger.GetExpression("departments[$i].OrgagnizationalRoleId"); Write-Host $a.Value $i }

The author for the idea can be found here: http://ogresoft.blogspot.ca/2013/06/how-to-write-loop-or-lambda-expression.html