Get current enumerator (iterator ?) in LINQ query. Like a current index in for loops
Is that possible to get current Enumerator (...or iterator? Don't know which tern is the correct one) in a LINQ query ?
For example, I try to create a XML output (via LINQ to XML) of all currently loaded assemblies.
Dim xmldoc As XDocument = New XDocument(
New XElement("Types",
Assembly.GetExecutingAssembly().GetReferencedAssemblies() _
.Select(Function(name) Assembly.Load(name)) _
.SelectMany(Function(assembly) assembly.GetTypes()) _
.Select(Function(type) New XElement("Type", type.FullName))))
Tho output looks like this.
<Types>
<Type>System.Object</Type>
<Type>FXAssembly</Type>
<Type>ThisAssembly</Type>
<Type>AssemblyRef</Type>
<Type>System.Runtime.Serialization.ISerializable</Type>
<Type>System.Runtime.InteropServices._Exception</Type>
.....
</Types>
is it possible to somehow get current "index" (counter?) from LINQ's Selects? I would like to use it in XML
<Types>
<Type ID="1">System.Object</Type>
<Type ID="2">FXAssembly</Type>
<Type ID="3">ThisAssembly</Type>
<Type ID="4">AssemblyRef</Type>
<T开发者_如何学运维ype ID="or-some-other-unique-id-#5">System.Runtime.Serialization.ISerializable</Type>
.....
</Types>
Yup - you just need to use the overload of Select
which takes a Func<TSource, int, TResult>
. So in C# it would be something like:
XDocument doc = new XDocument(new XElement("Types",
Assembly.GetExecutingAssembly().GetReferencedAssemblies()
.Select(name => Assembly.Load(name))
.SelectMany(assembly => assembly.GetTypes())
.Select((type, index) => new XElement("Type",
new XAttribute("ID", index + 1),
type.FullName))));
Sorry it's not in VB, but it's more likely to work this way - hopefully you can work out the translation :)
@V-Light,
You could do something like this to get your iterator index:
XDocument xml = new XDocument(New XElement("Items", from item in someItemsResourses where item.FullName.length => 5 orderby item descending //Get Iterator Index here and make use of it as you wish let currIndex = someItemsResourses.IndexOf(item) select new XElement("item", new XAttribute("id", ?how?), item.FullName)))
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