File Operations in C#

Question

Can u please help me with the Following file access mode

if we open a file with the following modes what will be the output?

l  "r":   Reading access (if File not exists what this will do)

l  "w":   Write-in access (if File not exists what this will do)

l  "a":   Access write-in [ appending ] (if File not exists what this will do)

Answer 1

Why don`t you try by yourself ?

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Hannes

If you have got questions about this, just ask.

In a perfect world,
users would never enter data in the wrong form,
files they choose to open would always exist
and code would never have bugs.

C# to VB.NET: http://www.developerfusion.com/tools/convert/csharp-to-vb/

Answer 2

http://msdn.microsoft.com/en-us/library/4z36sx0f(VS.80).aspx

Kindly have a look at the above link.

Regards,

Narendran Ponpandiyan

Answer 3

• "r": Reading access (if File not exists what this will do)

FileStream sRead= new FileStream(filename, FileMode.Open, FileAccess.Read, FileShare.Read);

Specifies that the operating system should open an existing file. The ability to open the file is dependent on the the value specified by FileAccess. A System.IO.FileNotFoundException is thrown if the file does not exist.

• l "w": Write-in access (if File not exists what this will do)

FileStream sWrite= new FileStream(filename, FileMode.Open, FileAccess.Write, FileShare.Write);

Specifies that the operating system should open an existing file. The ability to open the file is dependent on the the value specified by FileAccess. A System.IO.FileNotFoundException is thrown if the file does not exist.

l "a": Access write-in [ appending ] (if File not exists what this will do)

                FileStream sAppend= new FileStream(filename, FileMode.Append, FileAccess.Write, FileShare.Write);

Opens the file if it exists and seeks to the end of the file, or creates a new file. FileMode.Append can only be used in conjunction with FileAccess.Write. Any attempt to read fails and throws an ArgumentException.

More information, please refer:

http://msdn.microsoft.com/en-au/library/system.io.filemode(v=vs.80).aspx

http://msdn.microsoft.com/en-us/library/4z36sx0f(v=VS.71).aspx

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Mike Zhang[MSFT]
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