c# - What is the fastest way to check a type? -

-

instead of overloading function 100 times or creating 100 different comparers different types i've decided check type within 1 function.

for example i'm using default comparer compare values of set of types (primitives , strings) within 2 objects. contains following code:

public class defcomparer : icomparer<object> {     public int compare(object a, object b) {         .... // = a.gettype().getfield(field).getvalue(a); - not important question i'm showing a&b below different references         switch (a.gettype().name) {             case "byte":                 if ((byte)a == (byte)b) return 0;                 else if ((byte)a > (byte)b) return 1;                 else return -1;             case "uint16":                 if ((ushort)a == (ushort)b) return 0;                 else if ((ushort)a > (ushort)b) return 1;                 else return -1;             case "sbyte":                 if ((sbyte)a == (sbyte)b) return 0;                 else if ((sbyte)a > (sbyte)b) return 1;                 else return -1;             case "int16":                 ...

here i'm using switch statement said faster chain of if/else statements. a.gettype().name returns string dynamically obtained , method involves string comparisons. doesn't sound particularly fast me. need comparer fast technically possible because it's going used on large collections of data.

q: there faster way check type of object (that not involve string comparisons)? fastest possible way?

well have in hand. use typecode

        int = 10;         type t = a.gettype();          switch (type.gettypecode(t))         {             case typecode.boolean:                 break;             case typecode.byte:                 break;             case typecode.char:                 break;             case typecode.dbnull:                 break;             case typecode.datetime:                 break;             case typecode.decimal:                 break;             case typecode.double:                 break;             case typecode.empty:                 break;             case typecode.int16:                 break;             case typecode.int32:                 break;             case typecode.int64:                 break;             case typecode.object:                 break;             case typecode.sbyte:                 break;             case typecode.single:                 break;             case typecode.string:                 break;             case typecode.uint16:                 break;             case typecode.uint32:                 break;             case typecode.uint64:                 break;             default:                 break;         }

this supports primitives. custom objects write else if statements inside typecode.object.

i hope helps.


Comments

Post a Comment

Popular posts from this blog

html5 - What is breaking my page when printing? -

-
Image
i have questioner , don't know why when printing it's creating break before first question. live demo (link) i able resolve issue removing fieldset container had wrapped in.. having fieldset element causing of fields grouped together, , since not fit on first page, being pushed second page. removing fieldset element, able firefox print first 2 questions on page 1 identically chrome. it seems not new problem firefox , fieldset not playing nice found old bugzilla ticket 2008 has persisted , still being commented on in 2014 (link) if retaining fieldset important, found solution else came here (link) <script type='text/javascript'> $(window).bind('beforeprint', function(){ $('fieldset').each( function(item) { $(this).replacewith($('<div class="fieldset">' + this.innerhtml + '</div>')); } ) }); $(window).bind(
Read more

c# - must be a non-abstract type with a public parameterless constructor in redis -

-
when save object, got below error must non-abstract type public parameterless constructor in order use parameter 't' in generic type or method 'servicestack.redis.redisclient.store<t>(t) redisclass.getinstnace().store(msg); // error here redisclass.getinstnace().save(); as third party's class, can not edit how save object? could create wrapper around third party object call constructor, store wrapper? e.g. public class mywrapper { public thirdpartyobject thirdpartyinstance { get; set; } public mywrapper() { thirdpartyinstance = new thirdpartyobject("constructors"); } }
Read more

ajax - PHP/JSON Login script (Twitter style) not setting sessions -

-
i'm having trouble getting twitter style login work properly, reason gets stuck at session_register("useremail"); session_register("userpass"); and doesn't redirect after it. if enter wrong account data, works , appropriate error message pops up. this full code: <?php if(empty($_post['email']) || empty($_post['password'])) { die(msg(0,"all fields required")); } if(!(preg_match("/^[\.a-z0-9_\-\+]+[@][a-z0-9_\-]+([.][a-z0-9_\-]+)+[a-z]{1,4}$/", $_post['email']))) die(msg(0,"you haven't provided valid e-mail")); $host="localhost"; $username="root"; $password="x"; $db_name="x"; $tbl_name="x"; mysql_connect("$host", "$username", "$password")or die("cannot connect"); mysql_select_db("$db_name")or die("cannot select db"); $useremail=$_post['email']; $userpass=
Read more