List<t> findall question - predicates?

[=?Utf-8?B?bWdvbnphbGVzMw==?=]

I have a List<tobject consisting of objects which in themselves consist of
BindingListView s of objects. When I want to search for a object value I
normally create a foreach loop and increment a counter to provide me a count.

How can I refactor the same function w/o the foreach and use findall instead?

faux data structure:
---------------------
->
| Customers
<t Orders
| Orders_Details
->

/*start code*/
foreach (Orders _o in _Customers.Orde rs)
{
if (_o.exists)
i = i + 1;
}

if (i == _Customers.Orde rs.Count)
mRet = true;
/*end code*/

/*start desired code*/

myList.findall( _o.quantity >1)

/*end desired code*/

I want to take advantage of the Findall method in the generics namespace.
thanks

[Nicholas Paldino [.NET/C# MVP]]

What is the call to exits on _o? From this code segment,

foreach (Orders _o in _Customers.Orde rs)
{
if (_o.exists)
i = i + 1;
}

if (i == _Customers.Orde rs.Count)
mRet = true;

The equivalent using FindAll is:

// See where the orders exists.
List<Tresults = _Customers.Orde rs.FindAll(dele gate(Orders _o) { return
_o.exists; });

// If the count is the same between the two, then set mRet = true.
if (_Customers.Ord ers.Count == results.Count)
// Set mRet to true.
mRet = true;

Of course, if you were setting mRet to false in the event that the count
was not equal, you could just do this:

mRet = (_Customers.Ord ers.FindAll(del egate(Orders _o) { return
_o.exists; }).Count == _Customers.Orde rs.Count);

Hope this helps.
--
- Nicholas Paldino [.NET/C# MVP]
- mv*@spam.guard. caspershouse.co m
"mgonzales3 " <mg********@dis cussions.micros oft.comwrote in message
news:AB******** *************** ***********@mic rosoft.com...

>I have a List<tobject consisting of objects which in themselves consist
of
BindingListView s of objects. When I want to search for a object value I
normally create a foreach loop and increment a counter to provide me a
count.

How can I refactor the same function w/o the foreach and use findall
instead?

faux data structure:
---------------------
->
| Customers
<t Orders
| Orders_Details
->

/*start code*/
foreach (Orders _o in _Customers.Orde rs)
{
if (_o.exists)
i = i + 1;
}

if (i == _Customers.Orde rs.Count)
mRet = true;
/*end code*/

/*start desired code*/

myList.findall( _o.quantity >1)

/*end desired code*/

I want to take advantage of the Findall method in the generics namespace.
thanks

[Ben Voigt]

"mgonzales3 " <mg********@dis cussions.micros oft.comwrote in message
news:AB******** *************** ***********@mic rosoft.com...

>I have a List<tobject consisting of objects which in themselves consist
of
BindingListView s of objects. When I want to search for a object value I
normally create a foreach loop and increment a counter to provide me a
count.

How can I refactor the same function w/o the foreach and use findall
instead?

faux data structure:
---------------------
->
| Customers
<t Orders
| Orders_Details
->

/*start code*/
foreach (Orders _o in _Customers.Orde rs)
{
if (_o.exists)
i = i + 1;
}

if (i == _Customers.Orde rs.Count)
mRet = true;
/*end code*/

This can be made faster in many cases by leaving the loop early:

foreach (Orders _o in _Customers.Orde rs)
{
if (!_o.exists)
return false;
}
return true;

To get the same result using a predicate, use List<T>.TrueFor All...

mRet = _Customers.Orde rs.TrueForAll(d elegate (Orders o) { return
o.exists; });

BTW, it's usually considered bad practice to use names starting with
underscores, although this maybe isn't as important in C# because there's no
macro substitution possible.