Which is faster ?

[sebs]

Imagine I have a variable that has a lot of text in it, let's call it strLargeString, and in it, there's string like {1}, {2}, {3}, etc.. what would be faster?

For x = 1 to 100
   strLargeString = Replace(strLargeString, "{" & x & "}", "replaced")
Next

Or

Loop through the string using InStr to find the first {, then the next } and replace it after and move to the next ?

The first option, I let VB internal function to do the work, which could be faster, but is always has to start from the beginning. The second option, I keep moving the cursor to towards the end...

What are your thoughs on this ?

[Hack]

In a situation like this, I would go with the For/Next.

Have you tried both ways and done any timings?

[sebs]

Have you tried both ways and done any timings?

No, not yet...

If the Replace function could return the location of the string replace, I could do my next replace from there. Unless I do a InStr just before my replace and then I tell the replace function to do it from there ?

[ganeshmoorthy]

if the numbers more than 100?

[sebs]

if the numbers more than 100?

Sorry, not sure I get what you are saying ?

A 100 was just for an example...

[MartinLiss]

Imagine I have a variable that has a lot of text in it, let's call it strLargeString, and in it, there's string like {1}, {2}, {3}, etc.. what would be faster?

For x = 1 to 100
   strLargeString = Replace(strLargeString, "{" & x & "}", "replaced")
Next

Or

Loop through the string using InStr to find the first {, then the next } and replace it after and move to the next ?

The first option, I let VB internal function to do the work, which could be faster, but is always has to start from the beginning. The second option, I keep moving the cursor to towards the end...

What are your thoughs on this ?

You can find out for yourself. Take a look at the Time code using GetTickCount example in my signature.

[brucevde]

The Replace function has a Start argument, but I don't understand why you need it or why you care where it starts. Replace changes all instances of the found string.

[Al42]

Bruce, his replace has to be dynamic, since he's replacing a whole lot of different substrings in the string.

[sebs]

Exactly Al42, Bruce, I am thinking sort of like a cursor, I would have something like "text text text{1}text text text{2}text text{3}text text text text" in my string, that's why I was think if it would be better to do my own searching with InStr or do it with Replace. Then I though about the start parameter in the replace, maybe it would be better.

Thanks Martin, I will look at it.

[Mitsukai]

using repalce like that is VERY slow, your arguments are not right.
since evry time it will loop trough the whole string while it has found its match already (count = -1)
maybe thats why bruce got confused

try this instead(out of hand) i cant think of anything faster

dim iX as long
dim iY as long
dim iZ as long
 
iz = len("replaced")
ix = instr(1, strLargeString, "{", vbtextcompare)
do while ix > 0
  iy = iy +1
  strLargeString = Replace(strLargeString, "{" & iy & "}", "replaced", ix, 1, vbtextcompare)
  ix = instr(ix + iz, strLargeString, "{", vbtextcompare)
loop