uniqueidentifier

问题 Background I'm trying to get obtain a unique identifier out of a computer and want to be able to reliably return the same MAC address each time. Trust me I have my reasons for using MAC address and have read many posts about alternate unique id methods (and yes i've considered if they don't have any network cards). Problem The problem is in .NET i don't see anyway to tell whether a specific NetworkInterface is a physical hardware network card from something like a "Nortel IPSECSHM Adapter -

问题 This question already has answers here : How unique is the php session id (8 answers) Closed 6 years ago . When I call session_start() or session_regenerate_id() , PHP generates what appears to be a random string for the session ID. What I want to know is, is it just a random sequence of characters, or is it like the uniqid() function? Because if it's just random characters, couldn't you theoretically run into a conflict? If User A logged in and then User B logged in and, though highly

问题 I want to create a unique id but uniqid() is giving something like '492607b0ee414' . What i would like is something similar to what tinyurl gives: '64k8ra' . The shorter, the better. The only requirements are that it should not have an obvious order and that it should look prettier than a seemingly random sequence of numbers. Letters are preferred over numbers and ideally it would not be mixed case. As the number of entries will not be that many (up to 10000 or so) the risk of collision isn't

问题 I'm converting my application over to use factories instead of fixtures with Factory_Girl_Rails. I have the following factory defined: factory :requirement do sequence(:reqTitle) {|t| "Test Requirement #{t}"} ignore do categoryName " " categoryAbbr " " end reqText "This is a test general requirement for the purpose of, um, testing things" status "Approved" factory :reqWithCat do category end factory :reqWithNamedCat do category {create(:category, catName: categoryName, catAbbr: categoryAbbr)}

问题 Because of jQuery, I've been able to indulge my laziness to the max, but the real benefit has been spending most time on the good stuff and less on the tedious. I'd like to further that. Currently, I'll have some HTML like so: <div id="id1"></div> <div id="id2"></div> <div... and so on. Then, I'll call ajax , expecting the object "ids" to be the same as the div ids like so: $.ajax({ success: function (msg) { $("#id1").text(msg.id1); $("#id2").text(msg.id2); $("#... and so on. Can this be

问题 I was considering hashing small blocks of sensitive ID data but I require to maintain the full uniqueness of the data blocks as a whole once obfuscated. So, I came up with the idea of encrypting some publicly-known input data (say, 128 bits of zeroes), and use the data I want to obfuscate as the key/password, then throw it away , thus protecting the original data from ever being discovered. I already know about hashing algorithms, but my problem is that I need to maintain full uniqueness

问题 I want to implement "do once" pattern that allows me to avoid writing 3 things: declaring var first = true if(first) Do(...) statement inside repeated block of code first = false assignment inside repeated block of code I also want to avoid workarounds like these: manually maintaining and passing unique identification into Do function defining once context variable multiple times So my code should look as simple as this: using(var once = new Once()) foreach(var it in new[]{1,2,3}){ once.Do(()

问题 Say I have: struct S{ void f(int); float g(int,int); void h(int); } #define UID(w) /* how to do it? */ cout << UID(S::f); cout << UID(S::g); cout << UID(S::h); I need some way of creating a unique number, string or address for each member. This is because I'm going to be using: #define BIND(foo) Generate<decltype(&foo), &foo>::call u = & BIND(S::f) v = & BIND(S::g) w = & BIND(S::h) i.e. BIND generates an associated C-style function Here is a sketch of the generator: template< typename F f >

问题 I'm wondering how SQL Server orders data that is returned from a query and the Id columns of the respective tables are all of type uniqueidentifier. I'm using NHibernate GuidComb when creating all of the GUIDs and do things like: Sheet sheet = sheetRepository.Get(_SheetGuid_); // has many lines items IList<SheetLineItem> lineItems = sheet.LineItems; I'm just trying to figure out how they'll be ordered when I do something like: foreach (SheetLineItem lineItem in lineItems) I can't see to find

问题 I'm wondering how SQL Server orders data that is returned from a query and the Id columns of the respective tables are all of type uniqueidentifier. I'm using NHibernate GuidComb when creating all of the GUIDs and do things like: Sheet sheet = sheetRepository.Get(_SheetGuid_); // has many lines items IList<SheetLineItem> lineItems = sheet.LineItems; I'm just trying to figure out how they'll be ordered when I do something like: foreach (SheetLineItem lineItem in lineItems) I can't see to find