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Using Arrays for String Concatenation

In response to my previous post about using Java for String concatenation instead of ColdFusion’s concatenation operator, Greg has given me an interesting tip. It turns out that ArrayAppend() is a LOT quicker than regular concatenation, and the StringBuffer class! If you’re generating a CSV string, all you have to do is put each line into an array element using the ArrayAppend() method. Once all lines have been appended, convert the array to a list using the ArrayToList() method, using #chr(13)##chr(10)# as the delimiter. I decided to run the same sorts of tests that I have before. This time, I compared concatenating a string with regular string concatenation, the ArrayAppend method and the Java StringBuffer class. Using ArrayAppend was certainly the quicker of the three – by a long way. So, if you’re building a small-medium length string, then ArrayAppend is the way to go. However, a word of caution. If you are creating a large CSV file, then use the Java methods I have discussed before.


Code Examples

Regular string concatenation <cftimer type="inline" label="Regular concentation"> <cfscript> iNrTimesToLoop =; sStringToConcat = "The quick brown fox jumped over the fence: "; sString = ""; for (x=1; x LTE iNrTimesToLoop; x=x+1) { sString = sString & sStringToConcat & x; } </cfscript> </cftimer> ArrayAppend <cftimer type="inline" label="ArrayAppend"> <cfscript> iNrTimesToLoop =; sStringToConcat = "The quick brown fox jumped over the fence: "; aString = ArrayNew(1); for (x=1; x LTE iNrTimesToLoop; x=x+1) { temp = ArrayAppend(aString, sStringToConcat & x); } // Convert back into a string sString = ArrayToList(aString, "#chr(13)##chr(10)#"); </cfscript> </cftimer>

My new baby girl...

Eight weeks ago, my wife gave birth to our beautiful baby girl Tahni. She came in at 9 pounds 4 oz, so she was a big one! It’s been a big learning curve, hence why I haven’t posted in quite some time.

I'll be doing some follow up posts to my concatenation post, and also some new stuff I've been doing in Java.