Android Question charAT and " " (space value) doesn't work !

[DALB]

Hello everyone.

I only want to do a little thing which doesn't work. Here is the code:

Do While co.CharAt(0)=" "
    co=co.SubString(1)
Loop

I use it to control element of an array (or list).
This function doesn't extract the " " character:

' value' doesn't become 'value' !!!

Is there a way for making this easily ?

thks for any answer !

 

[Star-Dust]

Do While co.SubString2(0,1)=" "
    co=co.SubString(1)
Loop

Or

Do While co.StartWith(" ")
    co=co.SubString(1)
Loop

Or

Do While co.indexOf(" ")=0
    co=co.SubString(1)
Loop

But i prefear

co=co.Trim

 

[agraham]

  Dim co As String = "    fred"
  Do While co.CharAt(0)=" "
      co=co.SubString(1)
      Log(co.Length)
  Loop
  Log(co)

'Logs
'7
'6
'5
'4
'fred

In what way doesn't this work for you? It seems to work fine for me

 

[DALB]

Thanks all for answering the complete sub code is

    curs=Starter.SQL1.ExecQuery("SELECT * FROM bnotes")
    If curs.RowCount=0 Then Return
    For i=0 To curs.rowcount-1
        curs.Position=i
        Dim nid As Int=curs.GetInt("id")
        Dim co As String=curs.GetString("collection")
        Do While co.CharAt(0)=" "
            co=co.SubString(1)
        Loop
            Starter.SQL1.execquery("UPDATE bnotes SET collection='" & co & "' WHERE id=" & nid)
    Next

Agraham, the code doesn't want to give me the right anwser !!!
Star-Dust, each of your proposals doesn't work too !!!

!!!

I'll restart B4A...soon

 

[DALB]

After restarting B4A, the behaviour remains the same !!!
...I'm looking for...

 

[DALB]

replacing " " by chr(32) has any effect too !!!

 

[Sandman]

I haven't tested, but I'm guessing it's something weird with the cursor going on. Seems like a good time to point to #6:

[B4X] "Code Smells" - common mistakes and other tips

"Code smells" are common patterns that can indicate that there is a problem in the code. A problem doesn't mean that the code doesn't work, it might be that it will be difficult to maintain it or that there are more elegant ways to implement the same thing. Remember that not everything is clear...

www.b4x.com

And #21:

[B4X] Features that Erel recommends to avoid

Many things have changed in B4X and also in the underlying platforms. I will try to list here all kinds of (old) features that have better alternatives. B4X is backward compatible so these features still work. The recommendations are more relevant for new projects or when implementing new...

www.b4x.com

Given the weird results you're getting, I'd try changing to a ResultSet and also to just use co.Trim, like @Star-Dust proposed. No need to be overly complicated about it. (Unless you really want to save trailing spaces in your string, of course.)

 

[Star-Dust]

make sure the string is not null.

In any case, I believe that the problem is not. it is in the code but in the content of the string

 

[DALB]

thanks to all!
when I translate the first char with Asc(co.CharAt(0)), i can read 32 which is the asc code of the space character. But with all your proposals, i'm stuck !
I continue to look for, to understand what or where is the...bug !

 

[Sandman]

Add inside loop to better understand what you're dealing with:

Log(co)

 

[Star-Dust]

So this should work

log(asc(co.CharAt(0)))
Do While asc(co.CharAt(0))=32
    co=co.SubString(1)
    log(asc(co.CharAt(0)))
Loop

 

[Sandman]

I doubt it should work.

 

[DALB]

for you two, the log gives me the good answers.
so, Why can't I record them correctly in the base ?
I really don't understand what happens !!

 

[DonManfred]

I really don't understand what happens !!

We too.

Upload a small project showing the issue so we can try by ourselfs.

 

[Star-Dust]

Why don't you do the whole thing with an sql command?

Starter.SQL1.ExecNoQuery("UPDATE  bnotes SET collection = LTRIM(collection)")

 

[DALB]

Star-dust : Yes I've thought about this, but, even if I can find an issue out of B4A, I like to know why the problem exists in B4A !

DonManfred, here is the zip.

 

[Mahares]

I like to know why the problem exists in B4A !

This line is wrong:

Starter.SQL1.execquery("UPDATE bnotes SET collection='" & coo & "' WHERE id=" & nid)

It should be:

Starter.SQL1.ExecNonQuery("UPDATE bnotes SET collection='" & coo & "' WHERE id=" & nid)

Make the change and you will be good to go. Bonne Chance

 

[DALB]

Damn ! even if I have 2 eyes, the brain was missing !
pfffff ! Yes, now it works !
How stupid I'm !
Thanks for looking for me ! As we say, that's better having many heads than one !

 

[DALB]

This team is extra ! Each time I come here, each time, I have answers coming from good people ! Thanks for this !