guid

问题 As it currently stands, this question is not a good fit for our Q&A format. We expect answers to be supported by facts, references, or expertise, but this question will likely solicit debate, arguments, polling, or extended discussion. If you feel that this question can be improved and possibly reopened, visit the help center for guidance. Closed 7 years ago . Pros: I can't remember "good" passwords anyway so remembering them is not an issue. they don't look like passwords they are darn near

问题 There is a good deal of info on GUIDs on the net and StackOverflow. Indeed endless questions about uniqueness. This is not a question about 2^128 uniqueness . My question is to determine just how random the first section , secifically the first four bytes of the GUID is in .NET . Based on research, it is supposedly the least significant 32 bits of timestamp. But how is timestamp converted? Just how random is this? Does anybody know how the first section is constructed by .NET and if is truly

问题 I have this function: function getProduct(id: string){ //return some product } where id is actually GUID. Typescript doesn't have guid type. Is it possible create type GUID manually? function getProduct(id: GUID){ //return some product } so if instead 'xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx' will be some 'notGuidbutJustString' then I will see typescript compilation error. Update: as David Sherret said: there is no way to ensure a string value based on regex or some other function at compile

问题 How can I generate GUIDs and UUIDs in R? I would like to be able to generate GUIDs based on the hardware etc. of the machine running the rsession. As a fallback, however, I would be happy to create UUIDs that comply with rfc4122. Is there a package that can create GUIDs? Otherwise, does someone have some RFC4122 compatible UUID code lying about? 回答1: The optimal choice for this now is the uuid package. It consists of one function ( UUIDgenerate ) that doesn't rely on R's internal random

问题 I need to generate a unique ID and was considering Guid.NewGuid to do this, which generates something of the form: 0fe66778-c4a8-4f93-9bda-366224df6f11 This is a little long for the string-type database column that it will end up residing in, so I was planning on truncating it. The question is: Is one end of a GUID more preferable than the rest in terms of uniqueness? Should I be lopping off the start, the end, or removing parts from the middle? Or does it just not matter? 回答1: You can save

问题 In my database, in one of the table I have a GUID column with allow nulls. I have a method with a Guid? parameter that inserts a new data row in the table. However when I say myNewRow.myGuidColumn = myGuid I get the following error: "Cannot implicitly convert type 'System.Guid?' to 'System.Guid'." 回答1: The ADO.NET API has some problems when it comes to handling nullable value types (i.e. it simply doesn't work correctly). We've had no end of issues with it, and so have arrived at the

问题 Is is possible to use GUID as primary Keys in SQLITE Database?If Possible which datatype can be used? 回答1: SQLite itself does not support GUID as internal type. Except that, it does! (sort of). Remember, in SQLite any string can be used as type name, and that includes GUID or UUID (read more about SQLite datatypes). According to those rules, GUID type has affinity NONE , which is the same as for BLOB fields. With this in mind, you can create column of GUID type, and use following rules to

问题 How are GUIDs generated in SQL Server? I understand that I should use newid() , but what is the algorithm that function uses? Is it a hash of the time/date? 回答1: The algorithm to create it is described here: http://en.wikipedia.org/wiki/Globally_Unique_Identifier Algorithm In the OSF-specified algorithm for generating new (V1) GUIDs, the user's network card MAC address is used as a base for the last group of GUID digits, which means, for example, that a document can be tracked back to the

问题 I'm trying to capture an event and reference a GUID to see which event it is. The code is below: DWORD WINAPI AvisionEventProc(LPVOID lpParam){ //HANDLE hEvent = * (HANDLE *) lpParam; // This thread's read event STINOTIFY pStiNotify; if (debug){ wprintf(L"Avision Event\n"); } while(true){ WaitForSingleObject(hAvisionEvent, INFINITE); wprintf(L"Event"); pStiDevice->GetLastNotificationData(&pStiNotify); if (pStiNotify.guidNotificationCode == GUID_STIUserDefined1){ wprintf(L"User defined 1");

问题 I have an external database that is feeding information to me. One saves their data as native GUID format and my other data source supplies standard .NET GUID format string. Is there a tidy way to convert from Native GUID to GUID Structure? Also is there any validation bit to determine if a provided value is a Native GUID or not? I can't seem to find any if there is one. The difference is as follows: typedef struct _GUID { DWORD Data1; WORD Data2; WORD Data3; BYTE Data4[8]; } GUID; Data1,