Servicio ScriptForge.TextStream

El servicio TextStream se utiliza para leer y escribir secuencialmente archivos abiertos mediante el servicio ScriptForge.FileSystem.

Los métodos OpenTextFile y CreateTextFile del servicio FileSystem devuelven una ocurrencia del servicio TextStream.

Line delimiters may be specified by the user. In input operations CR, LF or CR+LF are supported. In output operations, the default line delimiter is the one used by the operating system.

The line delimiter for the operating system where the macro is being executed can be accessed using the SF_String.sfNEWLINE property.

All operations needed to read from or write to a file (open, read/write and close) are presumed to happen during the same macro run.

Invocación del servicio

Los ejemplos siguientes en BASIC y Python utilizan el método OpenTextFile para crear un ejemplar del servicio TextStream.

    GlobalScope.BasicLibraries.LoadLibrary("ScriptForge")
    Dim FSO As Variant
    FSO = CreateScriptService("FileSystem")
    Set myFile = FSO.OpenTextFile("C:\Temp\ThisFile.txt", FSO.ForReading)
  

El archivo debe cerrarse con el método CloseFile después de que todas las operaciones de lectura o escritura se hayan ejecutado:

    myFile.CloseFile()
  

Optionally, the resources used by the TextStream instance can be released using the Dispose method:

    Set myFile = myFile.Dispose()
  

Los métodos del servicio TextStream se basan principalmente en las interfaces XTextInputStream y XTextOutputStream de UNO.

    from scriptforge import CreateScriptService
    fs = CreateScriptService("FileSystem")
    myFile = fs.OpenTextFile(r"C:\Temp\ThisFile.txt", fs.ForReading)
    # ...
    myFile.CloseFile()
    myFile = myFile.Dispose()
  

Propiedades

Para conocer más sobre los nombres de los conjuntos de caracteres, consulte la página Conjuntos de caracteres de la IANA (en inglés). Conviene saber que LibreOffice no admite todos los conjuntos de caracteres existentes.

CloseFile

Closes the current input or output stream and empties the output buffer if relevant. Returns True if the file was successfully closed.

myFile.CloseFile(): bool

ReadAll

Returns all the remaining lines in the text stream as a single string. Line breaks are not removed.

The resulting string can be split in lines either by using the Split built-in Basic function if the line delimiter is known, or with the SF_String.SplitLines method.

For large files, using the ReadAll method wastes memory resources. In such cases it is recommended to read the file line by line using the ReadLine method.

myFile.ReadAll(): str

Considere el archivo de texto «Alumnos.txt» con este contenido (un nombre por cada renglón):

    Herbie Peggy
    Hardy Jarrett
    Edith Lorelle
    Roderick Rosamund
    Placid Everette
  

The examples below in Basic and Python use the ReadAll and SplitLines methods to read the contents of the file into an array of strings:

    'Carga el servicio FileSystem
    Dim FSO : FSO = CreateScriptService("FileSystem")
    'Opens the text file with the names to be read
    Dim inputFile as Object
    Set inputFile = FSO.OpenTextFile("/home/user/Documents/Students.txt")
    'Reads all the contents in the input file as a single string
    Dim allData as String
    allData = inputFile.ReadAll()
    'Splits the string into an array
    Dim arrNames as Variant
    arrNames = SF_String.SplitLines(allData)
    ' (...)
    inputFile.CloseFile()
  

    fs = CreateScriptService("FileSystem")
    inputFile = fs.OpenTextFile("/home/user/Documents/Students.txt")
    allData = inputFile.ReadAll()
    arrNames = allData.split(inputFile.NewLine)
    # ...
    inputFile.CloseFile()
  

ReadLine

Returns the next line in the text stream as a string. Line breaks are removed from the returned string.

The AtEndOfStream test should precede the ReadLine method like in the example below.

An error will be raised if the AtEndOfStream was reached during the previous ReadLine or SkipLine method call.

myFile.ReadLine(): str

    Dim sLine As String
    Do While Not myFile.AtEndOfStream
        sLine = myFile.ReadLine()
        ' (...)
    Loop
  

    while not myFile.AtEndOfStream:
        sLine = myFile.ReadLine()
        # ...
  

SkipLine

Skips the next line in the input stream when reading a TextStream file.

This method can result in AtEndOfStream being set to True.

myFile.SkipLine()

WriteBlankLines

Writes a specified number of empty lines to the output stream.

myFile.WriteBlankLines(lines: int)

lines: The number of empty lines to write to the file.

WriteLine

Writes the given string to the output stream as a single line.

El carácter definido en la propiedad NewLine se utiliza como delimitador de renglones.

myFile.WriteLine(line: str)

line: The line to write, may be empty.

The examples below in Basic and Python create a text file in CSV format in which each line contains a value and its square until lastValue is reached.

    Sub SquaredValuesFile(lastValue as Integer)
        'Instantiates the FileSystem Service
        Dim FSO as Variant : FSO = CreateScriptService("FileSystem")
        'Crea un archivo de texto
        Dim myFile as Variant : myFile = FSO.CreateTextFile("/home/user/Documents/squares.csv")
        'Writes the Value and Value squared, separated by ";"
        Dim value as Integer
        myFile.WriteLine("Value;Value Squared")
        For value = 1 To lastValue
            myFile.WriteLine(value & ";" & value ^ 2)
        Next value
        'Cierra el archivo y libera recursos
        myFile.CloseFile()
        Set myFile = myFile.Dispose()
    End Sub
  

    def squared_values_file(lastValue):
        fs = CreateScriptService("FileSystem")
        myFile = fs.CreateTextFile("/home/user/Documents/squares.csv")
        myFile.WriteLine("Value;Value Squared")
        for value in range(1, lastValue + 1):
            myFile.WriteLine("{};{}".format(value, value ** 2))
        myFile.CloseFile()
        myFile = myFile.Dispose()
  

Todas las rutinas o identificadores BASIC de ScriptForge precedidas por guion bajo «_» están reservadas para uso interno. No deben utilizarse en macros BASIC o secuencias Python.