EM_STREAMOUT message

Causes a rich edit control to pass its contents to an application defined EditStreamCallback callback function. The callback function can then write the stream of data to a file or any other location that it chooses.

wParam

Specifies the data format and replacement options.

This value must be one of the following values.

Expand table

Value	Meaning
SF_RTF	RTF.
SF_RTFNOOBJS	RTF with spaces in place of COM objects.
SF_TEXT	Text with spaces in place of COM objects.
SF_TEXTIZED	Text with a text representation of COM objects.

The SF_RTFNOOBJS option is useful if an application stores COM objects itself, as RTF representation of COM objects is not very compact. The control word, \objattph, followed by a space denotes the object position.

In addition, you can specify the following flags.

Expand table

Value	Meaning
SFF_PLAINRTF	If specified, the rich edit control streams out only the keywords common to all languages, ignoring language-specific keywords. If not specified, the rich edit control streams out all keywords. You can combine this flag with the SF_RTF or SF_RTFNOOBJS flag.
SFF_SELECTION	If specified, the rich edit control streams out only the contents of the current selection. If not specified, the control streams out the entire contents. You can combine this flag with any of data format values.
SF_UNICODE	Microsoft Rich Edit 2.0 and later: Indicates Unicode text. You can combine this flag with the SF_TEXT flag.
SF_USECODEPAGE	Rich Edit 3.0 and later: Generates UTF-8 RTF and text using other code pages. The code page is set in the high word of wParam. For example, for UTF-8 RTF, set wParam to (CP_UTF8 << 16) | SF_USECODEPAGE | SF_RTF.

lParam

Pointer to an EDITSTREAM structure. On input, the pfnCallback member of this structure must point to an application defined EditStreamCallback function. On output, the dwError member can contain a nonzero error code if an error occurred.

This message returns the number of characters written to the data stream.

When you send an EM_STREAMOUT message, the rich edit control makes repeated calls to the EditStreamCallback function specified by the pfnCallback member of the EDITSTREAM structure. Each time it calls the callback function, the control passes a buffer containing a portion of the contents of the control. This process continues until the control has passed all its contents to the callback function, or until an error occurs.

Reference

EDITSTREAM

EditStreamCallback

EM_STREAMIN