为什么我的按钮输出WebForm_DoPostBackWithOptions？

I need my page to work when JavaScript has been disabled. But my button is outputting onclick="WebForm_DoPostBackWithOptions...". When I set CauseValidation="false" it disappears but I need validation. In what circumstances is WebForm_DoPostBackWithOptions outputted? And how can I get around this problem?I need my page to work when JavaScript has been