File函数 中的 file.write(str)函数

Python file方法write()将字符串str写入文件。没有返回值。由于缓冲，在调用flush()或close()方法之前，字符串可能不会实际显示在文件中。

file.write(str) - 语法

fileObject.write( str )

• str  -  这是要写入文件的字符串。

file.write(str) - 示例

以下示例显示write()方法的用法。

This is 1st line
This is 2nd line
This is 3rd line
This is 4th line
This is 5th line

#!/usr/bin/python

# Open a file in write mode
fo=open("foo.txt", "rw+")
print "Name of the file: ", fo.name

# Assuming file has following 5 lines
# This is 1st line
# This is 2nd line
# This is 3rd line
# This is 4th line
# This is 5th line

str="This is 6th line"
# Write a line at the end of the file.
fo.seek(0, 2)
line=fo.write( str )

# Now read complete file from beginning.
fo.seek(0,0)
for index in range(6):
   line=fo.next()
   print "Line No %d - %s" % (index, line)

# Close opend file
fo.close()

当无涯教程运行上面的程序时，它产生以下输出-

Name of the file:  foo.txt
Line No 0 - This is 1st line

Line No 1 - This is 2nd line

Line No 2 - This is 3rd line

Line No 3 - This is 4th line

Line No 4 - This is 5th line

Line No 5 - This is 6th line