• Статья

StreamWriter Constructor (String, Boolean, Encoding, Int32)

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When it is called by trusted applications, initializes a new instance of the StreamWriter class for the specified file on the specified path, using the specified encoding and buffer size. If the file exists, it can be either overwritten or appended to. If the file does not exist, this constructor creates a new file.

Namespace:  System.IO
Assembly:  mscorlib (in mscorlib.dll)

Syntax

'Declaration
<SecuritySafeCriticalAttribute> _
Public Sub New ( _
    path As String, _
    append As Boolean, _
    encoding As Encoding, _
    bufferSize As Integer _
)

[SecuritySafeCriticalAttribute]
public StreamWriter(
    string path,
    bool append,
    Encoding encoding,
    int bufferSize
)

Parameters

  • append
    Type: System.Boolean
    Determines whether data is to be appended to the file. If the file exists and append is false, the file is overwritten. If the file exists and append is true, the data is appended to the file. Otherwise, a new file is created.

Exceptions

Exception Condition
ArgumentException

path is an empty string ("").

-or-

path contains the name of a system device (com1, com2, etc).
ArgumentNullException

path or encoding is nulla null reference (Nothing in Visual Basic).
ArgumentOutOfRangeException

bufferSize is negative.
IOException

path includes an incorrect or invalid syntax for file name, directory name, or volume label syntax.
SecurityException

The caller does not have the required permission.
UnauthorizedAccessException

Access is denied.
DirectoryNotFoundException

The specified path is invalid; for example, it might refer to an unmapped drive.
PathTooLongException

The specified path, file name, or both exceed the system-defined maximum length. For example, on Windows-based platforms, paths must be less than 248 characters, and file names must be less than 260 characters.

Remarks

Platform Notes

Silverlight for Windows Phone Silverlight for Windows Phone

 This member has a SecurityCriticalAttribute attribute on Silverlight for Windows Phone, because the attribute was present in Silverlight 3. This attribute restricts this member to internal use. Application code that uses this member throws a MethodAccessException.

Version Information

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

XNA Framework

Supported in: Xbox 360, Windows Phone OS 7.0

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.