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ReadText Method

Reads specified number of characters from a text Stream object.

Syntax

  
String = Stream.ReadText ( NumChars)  

Parameters

NumChars
Optional. A Long value that specifies the number of characters to read from the file, or a StreamReadEnum value. The default value is adReadAll.

Return Value

The ReadText method reads a specified number of characters, an entire line, or the entire stream from a Stream object and returns the resulting string.

Remarks

If NumChar is more than the number of characters left in the stream, only the characters remaining are returned. The string read is not padded to match the length specified by NumChar. If there are no characters left to read, a variant whose value is null is returned. ReadText cannot be used to read backwards.

Note

The ReadText method is used with text streams (Type is adTypeText). For binary streams (Type is adTypeBinary), use Read.

Queries that result in a large amount of XML data being returned through the ReadText method of the ActiveX Data Object (ADO) Stream object may take a great deal of time to execute; if this is done in a COM+ component that is invoked from an ASP page, the user's session may time out. ADO converts Stream object data from UTF-8 encoding to Unicode; the frequent memory reallocation involved in conversion of such a large quantity of data at once is quite time-consuming. To resolve, make repeated calls to the ReadText method of the ADO command object, and specify a smaller number of characters. Tests have shown that a value equivalent to 128K (131,072) is optimal. Response time decreases as this value is decreased. For more information, see Knowledge Base article 280067, "PRB: Retrieving very large XML Documents from SQL Server 2000 by using ReadText method of ADO stream object may be slow", in the Microsoft Knowledge Base at https://support.microsoft.com.

Applies To

Stream Object (ADO)

See Also

Read Method