资源描述：
《visual basic 6 string functions》由会员上传分享，免费在线阅读，更多相关内容在教育资源-天天文库。
1、VisualBasic6StringFunctionsVBhasnumerousbuilt-instringfunctionsforprocessingstrings.MostVBstring-handlingfunctionsreturnastring,althoughsomereturnanumber(suchastheLenfunction,whichreturnsthelengthofastringandfunctionslikeInstrandInstrRev,whichreturna
2、characterpositionwithinthestring).Thefunctionsthatreturnstringscanbecodedwithorwithoutthedollarsign($)attheend,althoughitisFunction:LenDescription:ReturnsaLongcontainingthelengthofthespecifiedstringSyntax:Len(string)Wherestringisthestringwhoselength(
3、numberofcharacters)istobereturned.Example:1.lngLen=Len("VisualBasic") 'lngLen=12 Function:Mid$(orMid)Description:Returnsasubstringcontainingaspecifiednumberofcharactersfromastring.Syntax:Mid$(string,start[,length])TheMid$functionsyntaxhastheseparts:
4、stringRequired.Stringexpressionfromwhichcharactersarereturned.startRequired;Long.Characterpositioninstringatwhichtheparttobetakenbegins.Ifstartisgreaterthanthenumberofcharactersinstring,Midreturnsazero-lengthstring("").lengthOptional;Long.Numberofcha
5、racterstoreturn.Ifomittedoriftherearefewerthanlengthcharactersinthetext(includingthecharacteratstart),allcharactersfromthestartpositiontotheendofthestringarereturned. Example: 1.strSubstr=Mid$("VisualBasic",3,4) 'strSubstr="sual"Note:Mid$canalsob
6、eusedontheleftsideofanassignmentstatement,whereyoucanreplaceasubstringwithinastring.1.strTest="VisualBasic"2.Mid$(strTest,3,4)="Chen"èResult:ViChenBasic1. 2.'strTestnowcontains"VixxxxBasic"InVB6,theReplace$functionwasintroduced,whichcanalsobeusedtore
7、placecharacterswithinastring. Function:Left$(orLeft)Description:Returnsasubstringcontainingaspecifiednumberofcharactersfromthebeginning(leftside)ofastring.Syntax:Left$(string,length)TheLeft$functionsyntaxhastheseparts:stringRequired.Stringexpressionf
8、romwhichtheleftmostcharactersarereturned.lengthRequired;Long.Numericexpressionindicatinghowmanycharacterstoreturn.If0,azero-lengthstring("")isreturned.Ifgreaterthanorequaltothenumberofcharactersinstring,theentirestringisreturned. Example:1.strSubstr=
