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AIOFile

サマリー

Contains methods that perform file-related operations such as seek, tell, read, and write.

ディスカッション

This class cannot be instantiated directly. An instance of this class is returned by the AIO object's open method.

プロパティ

名前 説明 データ タイプ

cloud

(読み取り専用)

An instance of a class that has cloud-specific methods. It is used to retrieve details of the cloud store that was used when the AIOFile object was created.

Returns an CloudFileOp object.

cloud_io = AIO(r"C:\data\datacloud.acs")
rcsfile = cloud_io.open(r'testfile.txt', 'r')
rcsfile.cloud.clearcache()

Object

方法

close()

Flushes and closes the open file handle.

For cloud stores, the cloud BLOBs are generated at closing.

rcsfile = cloud_io.open(r'cog.txt', 'r')
rcsfile.close()

flush()

Flushes the write buffers of the file.

rcsfile = cloud_io.open(r'cog.txt', 'r')
rcsfile.flush()

read(size)

Reads data from an object and returns binary or text depending on the opened items.

名前 説明 データ タイプ

size

The number of bytes that will be read. A value of -1 reads all the content.

Integer

戻り値

データ タイプ 説明

String

Returns binary or text (bytes or string) depending on the opened items.

from arcpy import AIO
cloud_io = AIO(r"C:\data\datacloud.acs")
rcsfile = cloud_io.open(r'testfile.txt', 'r')
rcsfile.read(size=4)
rcsfile.close()
from arcpy import AIO
cloud_io = AIO(r"C:\data\datacloud.acs")
with cloud_io.open(r'testfile.txt', 'r') as rcsfile:
    rcsfile.read(size=4)

rewind()

Resets the stream position to the start.

cloud_io = AIO(r"C:\data\datacloud.acs")
rcsfile = cloud_io.open(r'testfile.txt', 'r')
rcsfile.rewind()

seek(offset, {whence})

Changes the stream position to the specified byte offset.

名前 説明 データ タイプ

offset

The number of bytes that will be read. A value of -1 reads all the content.

The default value is -1.

Integer

whence

(オプション)

Specifies how the file position indicator will be set.

  • os.SEEK_SET—The position will be set relative to the beginning of the file.

  • os.SEEK_CUR—The position will be set relative to the current file position.

  • os.SEEK_END—The position will be set relative to the end of the file.

A nonzero value for os.SEEK_CUR or os.SEEK_END is not supported for local files when the file is opened in a nonbinary mode.

Object

import os
rcsfile = cloud_io.open(r'cog.txt', 'r')
rcsfile.seek(offset=6, whence=os.SEEK_CUR)

tell()

Returns the current stream position.

戻り値

データ タイプ 説明

Integer

The current stream position.

rcsfile = cloud_io.open(r'cog.tif', 'rb')
print(rcsfile.tell())

write(b)

Writes data to a local file or cloud object.

名前 説明 データ タイプ

b

The data that will be written.

String

戻り値

データ タイプ 説明

Integer

The number of bytes written.

from arcpy import AIO
local_io = AIO(r"C:\data")
rcsfile = local_io.open(r'testfile.txt', 'r')
rcsfile.write("This is a test file.")
rcsfile.close()
from arcpy import AIO
cloud_io = AIO(r"C:\data\datacloud.acs")
rcsfile = cloud_io.open(r"C:\data\info\datafile.txt", 'w', mime={'Content-Type': 'text/plain'})
rcsfile.write("This is a test file.")
rcsfile.close()
# Using with statement (context manager to close the opened file)
cloud_io = AIO(r"C:\data\datacloud.acs")
with cloud_io.open(r"C:\data\info\datafile.txt", 'w', mime={'Content-Type': 'text/plain'}) as rcsfile:
    rcsfile.write("This is a test file.")