if you are searching for a value in an array...converting to a string and then searching for that string may have a few properties you might not want...
first of all, converting the array to a string does take some extra time to process. Secondly there is a difference in how a computer checks for something in an array as opposed to how it checks for something in a string. Hashing algorithms (etc) aside...if a computer checks for a word in an array...it goes to each point in the array and says "is this it?" and depending on yes or no it goes onto the next element in the array... if you have the array: apples bananas oranges and search for oranges, it does 3 string tests...tests apples, tests bananas, tests oranges. if you make this into a string and get: applesbananasoranges and search for oranges, it starts at the first a and tests if starting there, it contains the word "oranges" it doesnt so it moves down a letter to the p, then the next p, then the l, then the e and so on until it gets to the o and returns success...this in effect is 13 string compares...compare 3 to 13 and remember this is only a 3 element array, imagine if it were 50! Even if it seems more cumbersome to test row by row, it is in fact more efficient. Lasty theres a problem of false positives, they are unlikely but very possible. if you have the array: oranges apples bananas sap and make it into the string: orangesapplesbananassap and search for "sap" you will notice in the string there are 2 occurences (end of oranges running into the begining of apples) while in the array there is only 1. Gotta be careful with that one, but it can be solved by seperating the words with spaces when you make the array by changing csuffix to ' ' (space). hope this helps some (: ----- Original Message ----- From: "David Shelley" <[EMAIL PROTECTED]> To: "Multiple recipients of list witango-talk" <[EMAIL PROTECTED]> Sent: Tuesday, December 03, 2002 2:29 PM Subject: RE: Witango-Talk: RE: Array to String > To convert an array to a string you can use the <@var> tag. > <@var yourArray aprefix='' asuffix='' rprefix='' rsuffix='' cprefix='' > csuffix=''> > This will append all the values together in one string. > > To check if a value is in the array use > <@if expr="@@yourArray contains @@yourString"> > The contains operator acting on an array does an = on each element in the > array, so if any element in the array matches your string exactly then the > expression is true. > > Dave Shelley > [EMAIL PROTECTED] > > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED]]On Behalf Of Wilcox, Jamileh > Sent: Tuesday, December 03, 2002 4:44 PM > To: Multiple recipients of list witango-talk > Subject: Witango-Talk: RE: Array to String > > > Or, alternatively, is there a way to see if something is in an array, > without having to loop through the rows? > > > -----Original Message----- > > From: Wilcox, Jamileh > > Sent: Tuesday, December 03, 2002 3:41 PM > > To: 'Witango-Talk' > > Subject: Array to String > > > > Is there anything in Witango that acts like the Javascript > > JOIN method (i.e., just converts an array to a delimited > > string)? It sure would make life easier sometimes. > > > > Thanks. j > ________________________________________________________________________ > TO UNSUBSCRIBE: send a plain text/US ASCII email to [EMAIL PROTECTED] > with unsubscribe witango-talk in the message body > > ________________________________________________________________________ > TO UNSUBSCRIBE: send a plain text/US ASCII email to [EMAIL PROTECTED] > with unsubscribe witango-talk in the message body ________________________________________________________________________ TO UNSUBSCRIBE: send a plain text/US ASCII email to [EMAIL PROTECTED] with unsubscribe witango-talk in the message body
