Consiglio :
Codice PHP:
string tipoimg = file1.PostedFile.ContentType;
if ( (tipoimg == "image/jpeg") || (tipoimg == "image/gif") )
oppure come diceva Pietro
Codice PHP:
public bool IsImage(string fileName)
{
string ext = Path.GetExtension(fileName).ToLower();
bool imageFlag = false;
if (ext != null)
{
switch (ext)
{
case ".emf" : // Enhanced Windows metafile image format
case ".exif" : // Exchangable Image Format
case ".ico" : // Windows icon image format (extension .ico)
case ".wmf" : // Windows metafile image format (extension .wmf)
case ".png" : // Specifies the W3C Portable Network Graphics image format (extension .png)
case ".gif" : // Graphics Interchange Format image format (extension .gif)
case ".bmp" : //Bitmap image format (extension .bmp)
case ".tiff" : // Tag Image File Format (extension .tif)
case ".tif" : // Tag Image File Format (extension .tif)
case ".jpeg" : // Joint Photographic Experts Group image format (extensions .jpg, .jpeg)
case ".jpg" : imageFlag = true; break; // Joint Photographic Experts Group image format (extensions .jpg, .jpeg)
default: imageFlag = false; break; // Not a supported file type.
} // switch (ext)
} // if (ext != null)
else
imageFlag = false;
return imageFlag;
} // bool IsImage(string fileName)