求CFileDialog::SetDefExt的使用说明

Call this function to set the default file name extension for an Explorer-style Open or Save As common dialog box.

void SetDefExt(
LPCSTR lpsz
);
Parameters
lpsz
A pointer to a string containing the default extension to use for the dialog box object. This string must not contain a period (.).

Remarks
The dialog box must have been created with the OFN_EXPLORER style; otherwise, the function will fail with an assertion.

Requirements
Header: afxdlgs.h

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