BString: Add ScanWithFormat convenience method.

headers/os/support/String.h

@@ -61,6 +61,12 @@ public:
 								va_list args)
 								__attribute__((__format__(__printf__, 2, 0)));
 
+			int				ScanWithFormat(const char* format, ...)
+								__attribute__((__format__(__scanf__, 2, 3)));
+			int				ScanWithFormatVarArgs(const char* format,
+								va_list args)
+								__attribute__((__format__(__scanf__, 2, 0)));
+
 			// Substring copying
 			BString&		CopyInto(BString& into, int32 fromOffset,
 								int32 length) const;

src/kits/support/String.cpp

@@ -474,6 +474,25 @@ BString::SetToFormatVarArgs(const char* format, va_list args)
 }
 
 
+int
+BString::ScanWithFormat(const char* format, ...)
+{
+	va_list args;
+	va_start(args, format);
+	int result = ScanWithFormatVarArgs(format, args);
+	va_end(args);
+
+	return result;
+}
+
+
+int
+BString::ScanWithFormatVarArgs(const char* format, va_list args)
+{
+	return vsscanf(fPrivateData, format, args);
+}
+
+
 //	#pragma mark - Substring copying