问不能隐式地将类型'System.Linq.IQueryable<TMS.Models.CustomAsset>‘转换为“System.Collections.Generic.ICollection”

EN

public class CustomerCustomAssetJoin
{
    public CustomAsset CustomAsset  { get; set; }
    public ICollection<CustomAsset> CustomAssets { get; set; }

} 

public CustomerCustomAssetJoin CustomerCustomAsset(string customerName)
{
    var customerAssets = tms.CustomAssets.Include(a => a.CustomAssetType).Where(a => a.CustomerName.ToLower() == customerName.ToLower());
    CustomerCustomAssetJoin caj = new CustomerCustomAssetJoin
    {
         CustomAsset = new CustomAsset {CustomerName = customerName },
         CustomAssets = customerAssets
    };
    return caj;  
 }

var customerAssets = tms.CustomAssets.Include(a => a.CustomAssetType).Where(a => a.CustomerName.ToLower() == customerName.ToLower());