Algorytmy i Programowanie Ćwiczenia: VBA (12)

Algorytmy i Programowanie Ćwiczenia: VBA (12)

(C) 2005 RoG@j
2005-05-23
Algorytmy i
Programowanie
Ćwiczenia: VBA (12)
Program zajęć (wg. TS…)
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Łańcuchy znakowe:
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© 2005 R. Robert Gajewski
[email protected]
http://rogaj.il.pw.edu.pl
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typ String,
kodowanie ASCI,
operacje na podciągach znakowych,
operatory konkatenacji (łączenia) i
porównania, funkcje tekstowe,
konwersje danych tekstowych i liczbowych
(jawne i niejawne)
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Program zajęć (wg. TS…)
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praca z zewnętrznymi źródłami danych,
podstawowe operacje I/O,
otwieranie i zamykanie plików dyskowych,
sekwencyjne przetwarzanie danych z/do plików
tekstowych, formatowanie,
systemowe operacje na plikach (kopiowanie,
usuwanie, sprawdzanie istnienia pliku o podanej
nazwie, itp.)
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AiPOI 2004/2005
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Returns a Long containing the number of characters in a
string or the number of bytes required to store a variable.
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Any valid string expression.
varname
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Any valid variable name.
One (and only one) of the two possible arguments
must be specified. With user-defined types, Len
returns the size as it will be written to the file.
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A valid named or user-defined format expression.
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Function Space()
Len (string | varname)
string
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Any valid expression.
format Optional.
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Len():
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Returns a Variant (String) containing an
expression formatted according to
instructions contained in a format expression.
Format (expression[, format])
expression Required.
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Function Len()
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Format Function
Pliki:
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Space Function: Returns a Variant (String)
consisting of the specified number of spaces.
Space (number)
The required number argument is the number
of spaces you want in the string.
The Space function is useful for formatting
output and clearing data in fixed-length
strings.
AiPOI 2004/2005
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(C) 2005 RoG@j
2005-05-23
FreeFile()
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Open Statement
Returns an Integer representing the next file number
available for use by the Open statement.
FreeFile [(rangenumber)]
The optional rangenumber argument is a Variant
that specifies the range from which the next free file
number is to be returned. Specify a 0 (default) to
return a file number in the range 1 – 255, inclusive.
Specify a 1 to return a file number in the range 256
– 511.
Use FreeFile to supply a file number that is not
already in use.
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Any valid file number.
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Any valid file number.
varlist Required.
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Comma-delimited list of variables that are assigned values
read from the file — can't be an array or object variable.
However, variables that describe an element of an array or
user-defined type may be used.
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Any valid file number.
outputlist Optional.
Expression or list of expressions to print.
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Close statement
Reads data from an open sequential file and
assigns the data to variables.
Input #filenumber, varlist
filenumber Required.
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Writes display-formatted data to a sequential
file.
Print #filenumber, [outputlist]
filenumber Required.
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Input # Statement
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One or more comma-delimited numeric
expressions or string expressions to write to a file.
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outputlist Optional.
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A valid file number in the range 1 to 511, inclusive. Use the
FreeFile function to obtain the next available file number.
Print # Statement
Write # Statement - Writes data to a
sequential file.
Write #filenumber, [outputlist]
filenumber Required.
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Keyword specifying the file mode: Append, Binary, Input,
Output, or Random. If unspecified, the file is opened for
Random access.
filenumber Required.
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String expression that specifies a file name — may include
directory or folder, and drive.
mode Required.
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Write Input statements
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Enables input/output (I/O) to a file.
Open pathname For mode As [#]filenumber
pathname Required.
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Concludes input/output (I/O) to a file opened using
the Open statement.
Close [filenumberlist]
The optional filenumberlist argument can be one or
more file numbers using the following syntax, where
filenumber is any valid file number:
If you omit filenumberlist, all active files opened by
the Open statement are closed.
When the Close statement is executed, the
association of a file with its file number ends.
AiPOI 2004/2005
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