如何在 VB.NET 中编写下面的算法代码?
Procedure logfile()
{
if "C:\textfile.txt"=exist then
open the textfile;
else
create the textfile;
end if
go to the end of the textfile;
write new line in the textfile;
save;
close;
}
Dim FILE_NAME As String = "C:\textfile.txt"
Dim i As Integer
Dim aryText(4) As String
aryText(0) = "Mary WriteLine"
aryText(1) = "Had"
aryText(2) = "Another"
aryText(3) = "Little"
aryText(4) = "One"
Dim objWriter As New System.IO.StreamWriter(FILE_NAME, True)
For i = 0 To 4
objWriter.WriteLine(aryText(i))
Next
objWriter.Close()
MsgBox("Text Appended to the File")
如果您在
True
的构造函数中将第二个参数设置为 System.IO.StreamWriter
,如果文件已存在,它将追加到文件,如果不存在,则创建一个新文件。
这也可以通过一行来实现:
System.IO.File.AppendAllText(filePath, "Hello World" & vbCrLf)
如果丢失,它将创建文件,追加文本并再次关闭它。
参见 MSDN,File.AppendAllText 方法。
For editing :
Try
Dim thefile As String = "C:\con_ip.txt" 'Put your path
Dim lines() As String = System.IO.File.ReadAllLines("C:\con_ip.txt")
lines(4) = q18.Text
System.IO.File.WriteAllLines(thefile, lines)
Catch ex As Exception
End Try