Redim

[Eugenious]

Whenever the Redim statement adds an array, I lose previous array values. can this be avoided without having to read the file twice?

example:
Pretend file(1) is a simple text file
dim linecnt as integer
dim StringIn as String, line() as String

linecnt = 0
do until eof(1)
Line Input #1, StringIn
linecnt = linecnt + 1
Redim line(linecnt)
line(linecnt) = StringIn
loop

[Y2J]

I have never actualy tried this, but this is what the msdn help file says

Preserving the Contents of Dynamic Arrays
Each time you execute the ReDim statement, all the values currently stored in the array are lost. Visual Basic resets the values to the Empty value (for Variant arrays), to zero (for numeric arrays), to a zero-length string (for string arrays), or to Nothing (for arrays of objects).

This is useful when you want to prepare the array for new data, or when you want to shrink the size of the array to take up minimal memory. Sometimes you may want to change the size of the array without losing the data in the array. You can do this by using ReDim with the Preserve keyword. For example, you can enlarge an array by one element without losing the values of the existing elements using the UBound function to refer to the upper bound:

ReDim Preserve DynArray(UBound(DynArray) + 1)

Only the upper bound of the last dimension in a multidimensional array can be changed when you use the Preserve keyword; if you change any of the other dimensions, or the lower bound of the last dimension, a run-time error occurs. Thus, you can use code like this:

ReDim Preserve Matrix(10, UBound(Matrix, 2) + 1)

good luck

[DrewDog_21]

Use the PRESERVE function after ReDim

linecnt = 0 
Do Until EOF(1) 
    Line Input #1, StringIn 
    linecnt = linecnt + 1 
    ReDim Preserve line(linecnt) 
    line(linecnt) = StringIn 
Loop

Also, when you post code examples, use the code tags ("code" in brackets [] at the beginning of the code and "/code" in brackets [] at the end). That preserves the formatting and makes it easier to read.

Suerte

Andrew

[Iain17]

You Need to use the Preserve keyword.

This will redim an array, and you will not lose any of the data.

Be warned that this takes a relativley long time, so try rediming as little as possible. One way to do this is to redim the array in steps of 10, or 50. Then when you have the final count you can redim it to the exact size.

''Pretend file(1) is a simple text file 
dim linecnt as integer 
dim StringIn as String, line() as String 

linecnt = 0 
do until eof(1) 
  Line Input #1, StringIn 
  linecnt = linecnt + 1
  Redim Preserve line(linecnt) As String
  line(linecnt) = StringIn 
loop



'or to redim it in steps of 50
Pretend file(1) is a simple text file 
dim linecnt as integer 
dim StringIn as String, line() as String 

linecnt = 0 
Redim line(50) As String

Do Until eof(1) 
  Line Input #1, StringIn 
  linecnt = linecnt + 1
  If linecount mod 50 = 0 then
    Redim Preserve line(linecnt + 50) as String
  End If
  line(linecnt) = StringIn 
Loop

Redim Preserve line(lineCount) as String

[DrewDog_21]

3 people posting the same answer, and all within one minute of each other! My, we are an intelligent bunch