Initializing ArrayList with constant literal
Can the ArrayList below be initialized directly wi开发者_运维问答thout the need for aFileExt string array?
private static string[] aFileExt =
{"css", "gif", "htm", "html", "txt", "xml" };
private System.Collections.ArrayList alFileTypes =
new System.Collections.ArrayList(aFileExt);
The line below is the goal, but my .Net Compiler does not like it:
private static System.Collections.ArrayList alFileTypes =
new System.Collections.ArrayList({"css","gif","htm","html","txt","xml"});
I am using the .net Micro Framework and thus do not have access to generic types.
C# 1 or 2:
private static ArrayList alFileTypes =
new ArrayList(new string[] {"css","gif","htm","html","txt","xml"});
C# 3 using an implicitly typed array:
private static ArrayList alFileTypes =
new ArrayList(new[] {"css","gif","htm","html","txt","xml"});
C# 3 using a collection initializer:
private static ArrayList alFileTypes =
new ArrayList{"css","gif","htm","html","txt","xml"};
Or create your own helper method:
public static ArrayList CreateList(params object[] items)
{
return new ArrayList(items);
}
then:
static ArrayList alFileTypes = CreateList("css","gif","htm","html","txt","xml");
Any reason why you're not using the generic collections, btw?
If you're using .NET 2.0 or greater, you should be using the generic List<T>
type (even if it's List<object>
, which would given you the same functionality as ArrayList
).
If you're using .NET 3.5 or greater, you can use this syntax:
private static List<string> fileTypes = new List<string>()
{
"css","gif","htm","html","txt","xml"
};
Either way, however, if you want to stick with ArrayList
, you can just do:
private static System.Collections.ArrayList alFileTypes =
new System.Collections.ArrayList(new object[] {"css","gif","htm","html","txt","xml"});
C# 3.0 with a generic List<T>
, rather than an ArrayList
:
private static List<string> alFileTypes =
new List<string> {"css","gif","htm","html","txt","xml"};
private static System.Collections.ArrayList alFileTypes =
new System.Collections.ArrayList(new string [] {"css","gif","htm","html","txt","xml"});
Try
private static System.Collections.ArrayList alFileTypes = new System.Collections.ArrayList(){"css","gif","htm","html","txt","xml"};
yes, just change
private static System.Collections.ArrayList alFileTypes =
new System.Collections.ArrayList({"css","gif","htm","html","txt","xml"});
to
private static System.Collections.ArrayList alFileTypes =
new System.Collections.ArrayList(new string[] {"css","gif","htm","html","txt","xml"});
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