zippy Posted March 21, 2009 Report Posted March 21, 2009 (edited) * / - Normal division* \ - Integer division (truncates the answer)* ^ - Exponentiation operator* * - Multiply* + - Plus* - - Minus* = - Equal* > - Greater Than* < - Less Than* <> - Not Equal* >= - Greater than or equal* <= - Less than or equal* AND - Defines a boolean value that is the AND of two valueso result = expression1 AND expression2* OR - Defines a boolean value that is the OR of two valueso result = expression1 OR expression2* XOR - Defines a boolean value that is the exclusive OR of two valueso result = expression1 XOR expression2* NOT - Defines an opposite boolean valueo A = NOT B* EQV - Performs a logical equivalence on two expressions (result is true if both expressions are true)o result = expression1 EQV expression2* IMP - Performs a logical implication on two expressionso result = expression1 IMP expression2* IS - Determines if 2 variables reference the same objecto result = object1 IS object2* LIKE - Determines if one string matches a patterno result = string LIKE pattern* MOD - Returns the integer remainder of a divisiono i = 27 MOD 5MathVB also provides built-in functions which can act on variables. Most are sel***xplanatory. In my experience, the VAL, RND, and ROUND functions are among the most valuable, so be sure to pay close attention to them!* Round - Rounds a number to a selectable number of decimal placeso result = round ( tempvariable,2 )* Val - Returns the numerical content of a stringo result = Val ("123.4")* Int - Returns an integer by truncating (different than Fix)o i = int ( tempvariable )* Fix - Returns an integer by truncating (different than Int)o i = fix ( tempvariable )* Hex - Returns the hexadecimal value of any numbero temp$ = hex ( tempvariable )* Oct - Returns the octal value of any numbero temp$ = oct ( tempvariable )* Tan - Returns the tangent of an angleo tempvariable1 = tan ( tempvariable2 )* Rnd - Returns a random number between 0 and 1o tempvariable1 = rnd* Randomize - Initializes the Rnd function so it gives different answers each timeo randomize* Sgn - Returns the sign of a numbero i = sgn ( tempvariable )* Sin - Returns the sine of an angleo tempvariable1 = sin ( tempvariable2 )* Cos - Returns the cosine of an angleo tempvariable2 = cos ( tempvariable )* Abs - Converts a number to a positive valueo i = abs ( tempvariable )* Sqr - Returns the square root of a numbero tempvariable1 = sqr ( tempvariable2 )* Log - Returns the base 10 logarithm of a numbero tempvariable1 = log ( tempvariable2 )* Atn - Returns the arctangent of an angleo tempvariable1 = atn ( tempvariable )* Partition - Sort of an oddball function but segregates values according to rangeso* Type Conversions - A variety of conversion functionso CBool, CByte, CCur, CDate, CDbl, CDec, CInt, CLng, CSng, CStr, CVarStrings* Left - Returns the left n characters of a stringo temp$ = left$ ( teststring$, 4 )* Right - Returns the right n characters of a stringo temp$ = right$ ( teststring$, 4 )* Trim - Removes leading and trailing spaces of a stringo temp$ = trim$ ( teststring$ )* LTrim - Removes only the leading spaces of a stringo temp$ = ltrim$ ( teststring$ )* RTrim - Removes only the trailing spaces of a stringo temp$ = rtrim$ ( teststring$ )* UCase - Makes all characters upper caseo temp$ = ucase$ ( teststring$ )* LCase - Makes all characters lower caseo temp$ = lcase$ ( teststring$ )* Mid - Returns n characters from a string, starting a any positiono temp$ = mid$ ( teststring$, 1, 4 )* Len - Returns the length of a string (how many characters it has)o temp$ = len ( teststring$ )* LSet - Positions a string inside another, flush to the lefto temp$ = lset ( teststring$ )* RSet - Positions a string inside another, flush to the righto temp$ = rset$ ( teststring$ )* Format - Returns a string formatted according to a user-defined formato temp$ = format$ ( teststring$, "####.0" )* String -o temp$ = left$ ( teststring$, 4 )* Chr - Returns the string representation of a numbero temp$ = str$ ( 32 )* Asc - Returns the ASCII code of a single charactero temp$ = asc ( "A" )* Space - Returns n spaceso temp$ = space$ ( 15 )* Instr - Determines if one string is found within a second stringo i = Instr (starthere, string1, string2)* InStrRev - Determine if one string is found in a second, starting at the endo i = InStrRev (string1, string2, start)* StrComp - Compares two stringso result = StrComp (string1, string2)* StrConv - Converts the case of a string's characterso StrConv (string, vbuppercase)* StrReverse - Reverses character order in a stringo StrReverse (string1)* Replace - Replaces each occurrence of a stringo Replace (bigstring, searchstring, replacementstring)* FormatCurrency - Returns a string using a currency formato FormatCurrency(var1, 2)* FormatDateTime - Returns a date or time expressiono FormatDateTime("3/2/99",vbShortTime)* FormatNumber - Returns a number formatted according to a variety of optionso FormatNumber(var1, 2)* FormatPerCent - Returns a number formated as a percento FormatPerCent(var1, 2)ArraysEvery programmer eventually uses arrays. Mostly they're pretty easy to understand. Take note, however, that you can resize an array with REDIM without losing the data. For details, see the PRESERVE keyword in the HELP entry on REDIM. If you use the LBound/UBound in your code instead of hard-coding the dimension of the array, you can later change the size of the array without touching your code!* Option Base - Determines whether the lowest range of an array is 0 or 1o option base 1* Erase - Erases all values of an arrayo erase (arrayname)* Dim - Creates an arrayo dim arrayname(25)* Redim - Resets the bounds of an array (has option to save values)o redim arrayname(28)* UBound - Returns the upper dimension of an arrayo i = ubound (arrayname)* LBound - Returns the lower dimension of an arrayo i = lbound (arrayname)* Filter - Returns a subset of an array based on a filtero Filter (inputarray, searchstring)* Array - Yes, there is a function called array. It returns an array that has been filled with data from a list. It allows you to put the actual data values in the code to avoid having the user input it or to avoid having to read it from a fileo ArrayName = Array (10, 20, 30)* Join - Concatenates strings within an arrayFile Handling (Generic)While VB is working on a better approach (FileSystemObject), the built-in file handling statements are still the only way to access data other than through the VB database capabilities. Your skills in this area can make or break your ability to work with various formats. The OPEN/CLOSE statements are critical to success, but the LOF, EOF, and LEN functions are used even more often! It's also a given that you'll use the DIR function regularly.* Dir - Returns a filename that matches a patterno temp$ = Dir ("*.*")* CurDir - Returns the current directoryo temp$ = CurDir* MkDir - Creates a directoryo mkdir ( "newdirectoryname" )* ChDir - Changes the current directory to a new locationo chdir ( "newdirectoryname" )* ChDrive - Changes the current driveo ChDirve "A"* RmDir - Removes the indicated directoryo rmdir ( "directoryname" )* Freefile - Returns an unused file handleo i = freefile* Open - Opens a file for access, locking it from other applicationso open "filename" for input as #1* Close - Closes a file so that other applications may access ito close #1* LOF - Returns the length of a file in byteso i = lof ( #1 )* EOF - Returns a boolean value to indicate if the end of a file has been reachedo statusvariable = eof ( #1 )* Name As - Renames a fileo name "filename1" as "filename2"* Kill - Deletes a fileo kill "filename"* Fileattr - Returns attribute information about a fileo i = int ( tempvariable )* GetAttr - Returns attributes of a file or directoryo i = GetAttr("cwindows\temp")* SetAttr - Sets the attributes of a fileo SetAttr pathname, vbHidden* Reset - Closes all disk files opened by the OPEN statemento Reset* FileDateTime - Returns data file was created or last editedo FileDateTime ( filename )* FileLen - Returns length of file in byteso FileLen ( filename )* FileCopy - Copies a file to a new nameo FileCopy sourcefile, destinationfile* Lock - Controls access to a part or all of a file opened by OPENo Lock #1* UnLock - Restores access to a part or all of a file opended by OPENo UnLock #1* Width # - Set the output line width used by the OPEN statemento Width #2, 80File Handling - ASCII-specificWhile VB is working on a better approach (FileSystemObject), the built-in file handling statements are still the only way to access data outside of a data base. Your skills in this area can make or break your ability to work with various formats. The OPEN/CLOSE statements are critical to success, but the LOF, EOF, and LEN functions are necessary to build useful code.* Line Input - Reads an entire line of ASCII texto line input #1, tempvariable$* Write - Puts data in a file, with separators for the datao write #1, tempvariable$* Print - Puts data in a file with no separatorso print #1, tempvariable$* Spc - Used in a print statement to move a number of spaceso Print #2, var1; spc(15); var2* Tab - Used in a print statement to move to TAB locationso Print #2, var1; Tab(20); var2File Handling - Binary-specificVB also support features which allow you to access a file on a byte-by-byte basis. The good thing about it is that you have more control, the bad thing is that you may have to write more code. Generally, a programmer will use the option (ASCII or Binary access) according to the least code he has to write. For binary access the Get/Put are equivalent to the Line Input and Print functions used in ASCII text file access. The big difference between the two is that binary access will read (Get) an exact number of bytes of data, and the reading can start at any byte within the file.* Get - Reads data from a fileo get #1, anyvariable* Put - Puts data into a fileo put #1, anyvariable* Seek - Moves the current pointer to a defined location in a fileo seek #1, 26* Inputo input #1, anyvariable* Loc - Returns current position with an open fileo i = Loc(#2)DeclarationsI probably get more questions about the functions in this section than about any other group. In general, the concepts are pretty simple, but the details of getting it exactly right can cause even experienced programmers trouble. Focus on understanding Dim/ReDim/Public/Private/Sub/Function/Type and Set. However, they're all useful at times, so bear down and commit these to memory. I'll try to add more text and tips on these than I have on the others.* Dim - Used to define a variable as a certain typeo i = dim i as integer, r as singleo You can use the Option Explicit to make sure that VB forces you to declare every variable you use. DIM is that simplest way to declare a variable* ReDim - Used to change the dimensions of a dynamic arrayo redim arrayname(37)o Don't be afraid of this one. You can use ReDim to create an array whose size grows by 1 every time you want to add a number to it. Then, the UBound tells you how many numbers you've added.* Static - Establishes a procedure variable which keeps its value between callso static i as integero For example, if you want to keep track of how many times you've been in a procedure, set a counter as STATIC and increment it by one for each visit to the procedure. It will never go away until the program is terminated.* Public - Creates a variable which can be accessed outside its own procedureo public i as integero Even if you're the only programmer writing code in your application, use of Private vs Public will help catch errors if you inadvertently try to access an out-of-scope variable* Private - Creates a variable that can be read only in its own procedure or module, according to where the declaration took place.o private i as integero Use this as often as possible to avoid unnecessary exposure of your variables to coding mistakes.* Sub - Defines a procedure which can execute a block of codeo Sub NewProcedure (var1 as integer, var2 as string)o Be sure to check out HELP for how to handle Sub arguments. There are more questions and mistakes made concerning the use of arguments than just about anything else I've seen.* Function - Declares a procedure which can return a valueo Function NewFunction (var1 as integer, var2 as string) as SINGLEo This is actually the most versatile of the Sub/Function procedure types. It can do anything a Sub can do as well as returning a value for use in an expression.* Call - Transfers control to a Sub or Function (is optional)o Call Procedure 1o Since the use of CALL is optional, forget you ever saw it* CallByName - Executes a method of an object or set/returns a propertyo CallByName(form1,procedurename,vbMethod)o The really cool thing about this is that you don't have to hardcode a procedure call. Just use a string variable with the name of the procedure to call.* Option Explicit - Instructs VB to force an explicit declaration of all variableso Option Explicito You're borderline stupid if you don't use it to catch typing errors. Set up the VB IDE to automatically include this in all projects.* Option Compare - Instructs VB on how to make string comparisonso Option Compare Binaryo This can add case-insensitivity for those times when you don't want to hard-code it* Option Private - Prevents a module's content from being referenced outside a project.o Option Private Moduleo Generally doesn't apply to most VB applications. If you find a good use for it let me know.* Property Get - Declares how to get the value of a propertyo Property Get Name()o You won't use this much until you get into creating classes of your own* Property Let - Declares how to assign a value to a propertyo Property Let Name()o You won't use this much until you get into creating classes of your own* Property Set - Declares how to set a variable reference to an objectoo You won't use this much until you get into creating classes of your own* Set - Assigns an object reference to a variableo Set X = form1.txtInputFromUsero Very useful for making code more readable or simply to cut down on how much typing you have to do!* Let - Precedes assignment of a value to a variableo Let i = 3o It's optional, no one uses, so forget you ever saw it* Type...End Type - Creates a user defined part type which consists of standard VB data typeso type anytypenameo one as stringo two as integero three as booleano End Typeo This is a really excellent way to keep several kinds of data under one variable name. Plus, you can PUT or GET a user-defined type with a single line of code.* Const - Creates a variable whose value is fixedo const anynameo Basically, use this to give easy to remember names to values. For example, suppose you use the value 37.2 a lot in your code, then if you put CONST MyAge = 37.2 in your code you'll be able to insert the MyAge where the 37.2 should have gone. Easier to type and easier to read. Also, you can chane the value of the constant by changing only the declaration line of code, rather than searching out every place the value was used!* Declare - Used to define a procedure that exists in another fileo declare functionname (arg1 as integer, arg2 as string) as integeroo ArrayName = Array (10, 20, 30)o Implements - Specifies a class to be implemented in a module+o Friend - Allows procedure to be callable from modules outside the class+o GetObject - Return a reference to an ActiveX component+o CreateObject - Creates and returns a reference to an ActiveX object+o GetAutoServerSettings - Returns information about the state of an ActiveX component's registration.+o Enum - Declares a type for an enumeration+o Event - Declares a user-defined event+o TypeName - Returns the type of data in a variable+o VarType - Returns the type of data in a variable+o DefType - Sets the default data type of variables+ DefInt A-Zo IS - A variety of data type or status checking options+ IsArray, IsBindable, IsBroken, IsDate, IsDirty, IsEmpty, IsError, IsMissing, IsNull, IsNumber, IsObject, IsReady, IsRootFolderDate/TimeThese functions are pretty sel***xplanatory so I've not added any extra comments to them.o Date - Gets the current dateo Time - Gets the current timeo Now - Gets the current date and timeo Timer - Returns the number of seconds since midnighto DateAdd - Adds a time interval to a dateo DateDiff - Returns how many time intervals there are between two dateso DateSerial - Returns the month/day/yearo DateValue - Returns the dateo Year - Returns the current yearo Month - Returns the current month (integer)o MonthName - Returns the text of the name of a montho Day - Returns the current dayo Hour - Returns the current houro Minute - Returns the current minuteo Second - Returns the current secondo TimeSerial - Returns a date with the hour/minute/secondo TimeValue - Returns the timeo WeekDay - Returns the current day of the week (integer)o WeekDayName - Returns the text of a day of the weekMiscellaneousIn this list you'll find some of the features of VB about which I get a lot of email questions! The MsgBox is easily the most used of the bunch. It handles all of the "Y/N" queries to your user so get to know it well. Also, the DoEvents, Shell, and Command functions are indispensable in certain occasions so make sure you know when they should be used.o MsgBox - A built-in dialog box that gives a message and allows a user input+ i = msgbox "Read this!", vbokonly, "Test Message"o DoEvents - Allows VB to complete pending tasks+ doeventso Shell - Executes a 2nd program from within the current program+ shell "notepad.exe"+ Note - VB does not wait for the Shell'd program to quit before executing the next line of code!o Command - Gives any text that followed a VB .EXE execution command+ temp$ = commando Environ - Returns the system environmental space content+ temp$ = environo Beep - Makes the computer beep once.+ beepo InputBox - A built-in dialog box that allows entry of a text string+ inputbox "Input a value!", 5o AddressOf - Provides an entry point for an external program to use a procedure+ AddressOf ( procedurename )o AppActivate - Activates an applications window+ AppActivate ( windowtitle )o RaiseEvent - Fires an event declared at module level+ RaiseEvent ProcedureNameo Load - Load an object+ load form1o Unload - Unload an object+ Unload form1o LoadPicture - Load a picture into a control property+ form1.picture = loadpicture (filename)o SavePicture - Save a picture to a file+ SavePicture(form1.picture,filename)o LoadResData - Load the data from a resource file+ LoadResData(index,format)o LoadResString - Load a string from a resource file+ LoadResString(index,format)o SendKeys - Send keys to another app as though they were from the keyboard+ Sendkeys {DOWN}o QBColor - Returns a value corresponding to the original QB values 0-15+ form1.backcolor = QBcolor (12)o RGB - Returns a color value by inputting the red, green, and blue parts+ form1.backcolor = RGB (12,128,256)o Me - Refers to the current object, usually the active form+ print Me.captionRegistryI've never quite understood why Microsoft got away from the use of an INI file. The ability to use a simple text editor to resolve problems with a program's settings was a key feature about INI files. Also, no matter how Windows crashed, the INI file was protected.+ temp$ = getsetting "TestApp", "SectionName", "KeyName", "defaultvalue"o GetAllSettings -Returns a list of key settings and their values+ GetAllSettings(appname,section)o SaveSetting - Save a value into the Registry+ savesetting "TestApp", SectionName, KeyDatao DeleteSetting - Deletes an entry from the registry+ deletesetting "TestApp", "SectionName", "Keyname"Loops and Conditional DecisionsWhile the event-driven model of VB has taken out a lot of the need for controlling the flow of your application, don't think for a second that you can get by without being an expert on these features of VB. Virtually every single procedure you'll ever write will have one or more of these in it. The concepts are simple, so take the time to become a master of each one! The For...Next and the Select Case statements are the two most used, so concentrate on them first.o If..Then..Else - Performs code based on the results of a test+ If A>5 Then Print "A is a bit number!"o For...Next - Loops a specified number of times+ For i = 1 to 5: print #1, i: next io For Each ... Next - Walks through a collection+ For Each X in Form1.controls: Next Xo While...Wend - Loops until an event is false+ while i < 5: i = i +1: wendo Select Case - Takes an action based on a value of a parameter+ select case i+ case 1 : print "it was a 1"+ case 2 : print "it was a 2"+ end selecto Do...Loop - Loops until conditions are met+ do while i < 5 : i = i + 1 : loopo IIF - Returns 1 of two parts, depending on the value of an expression+ result = IIF (testexpression, truepart, falsepart)o Choose - Selects and returns a value from a list of arguments+ Choose (index, "answer1", "answer2", "answer3")o With - Executes a series of statements on a single object+ With textbox1+ .Height = 100+ .Width = 500+ End Witho End - Immediately stops execution of a program+ Endo Stop - Pauses execution of a program (can restart without loss of data)+ Stopo Switch - Returns a value associated with the first true expression in a list+ result = Switch (testvalue1, answer1, testvalue2, answer2)o GoTo - Switches execution to a new line in the code+ GoTo Line1o GoSub ... Return - Switches execution to a new block of code and then returns+ GoSub Line1o On .. GoSub - Branch to a specific line of code then return at the next Return statement+ On Number GoSub Line1, Line2, Line3o On .. GoTo - Branch to a specific line of code+ On Number GoTo Line1, Line2, Line3Special ValuesThere are some keywords in VB which take on special meaning. Their use can be confusing at times, but you'll get used to the terminology as your programming experience grows.o True - A logical (Boolean) expression. In VB, its value is -1+ X = TRUEo False - A logical (Boolean expression. In VB, its value is 0+ X = FALSEo Nothing - Disassociates an object variable from an actual object+ Set X = Nothingo Null - Indicates that a variable has no valid data+ X = Nullo Empty - Indicates that a variable has not yet been initialized+ X = EmptyError HandlingTry as I might, I cannot create error free code! So, I turn to these VB features to help me figure out what went wrong.o On Error - Enables an error-handling routine+ On Error GoTo Line2 (if error occurs, go to line2)+ On Error Resume Next (if error occurs, continue executing next line of code)+ On Error Goto 0 (disables error handling)o Resume - Used to resume execution after a error-handling routine is finished+ Resume+ Resume Next+ Resume Line1o CVErr - Returns an error type variable containing a user-specific error number+ X = CVError(13)o Error - Simulates the occurrence of an error+ Error 23CalculationsFor those folks who want to use VB for performing routine investment calcuations, VB provides a variety of functions. Personally, I use them very infrequently, but I suspect they are used regularly by a lot of programmers. I've never gotten a single question in the mail about these functions!o DDB - Returns the depreciation of an asset for a specific time periodo FV - Returns the future value of an annuityo IPmt - Returns the interest payment of an investmento IRR - Returns the internal rate of return on a cash flowo MIRR - Returns a modified internal rate of return on a cash flowo NPer - Returns a number of periods for an annuityo NPV - Returns a present value of an investmento PPmt - Returns the principal payment of an annuityo PV - Returns the present value of an annuityo Rate - Returns the interest rate per period for an annuityo SLN - Returns the straight-line depreciation of an asseto SYD - Returns the sum-of-years' digits depreciation of an asset Edited March 21, 2009 by Mish blah blah Quote
-=(Alex_sm26)=- Posted March 21, 2009 Report Posted March 21, 2009 Mersi!!! chiar cautam, daca poti sa-mi dai ceva tutoriale in legatura cu VB. Quote
zippy Posted March 21, 2009 Author Report Posted March 21, 2009 cauta-ti singur..sant o gamada pe netwww.google.ro Quote
-=(Alex_sm26)=- Posted March 21, 2009 Report Posted March 21, 2009 Mersi pt. ajutor!Eu inainte sa te rog sa ma ajuti m-am documentat si nu gasesc nimic pe seama mea(sunt incepator) si alea de pe youtube...parerea mea ca-s magarii...apoi am vazut topic-ul tau si m-am gandit ca tu ma poti ajuta...in fine...Sal. Quote