為什么function無(wú)法獲取全局變量的值?為什么全局變量不起作用?
<!--為什么這里的function無(wú)法獲取全局變量的值?為什么全局變量不起作用?--> ????<script?type="text/javascript"> ????var?btn?=?document.getElementById('strHref'), ????????hpn?=?document.getElementById('hpn'); ???? ????function?showdiv()?{//展開(kāi)函數(shù)??? ????????hpn.style.display?=?'block'; ????????btn.innerHTML?=?'收起'; ????????btn.href?=?"javascript:hidediv();"; ????} ????function?hidediv()?{//收起函數(shù) ????????hpn.style.display?=?'none'; ????????btn.innerHTML?=?'展開(kāi)'; ????????btn.href?=?"javascript:showdiv();"; ????} ????</script>
從html調(diào)用函數(shù),頁(yè)面不能動(dòng)態(tài)顯示。
<script?type="text/javascript"> ????????function?showdiv()?{//展開(kāi)函數(shù) ????????var?btn?=?document.getElementById('strHref'), ????????????hpn?=?document.getElementById('hpn'); ????????????hpn.style.display?=?'block'; ????????????btn.innerHTML?=?'收起'; ????????????btn.href?=?"javascript:hidediv();"; ????????} ????????function?hidediv()?{//收起函數(shù) ????????var?btn?=?document.getElementById('strHref'), ????????????hpn?=?document.getElementById('hpn'); ????????????hpn.style.display?=?'none'; ????????????btn.innerHTML?=?'展開(kāi)'; ????????????btn.href?=?"javascript:showdiv();"; ????????} ????</script>
改成上面這樣的就沒(méi)有問(wèn)題了。
為什么function無(wú)法獲取全局變量的值?
為什么全局變量不起作用?
求解,謝謝:-D
2016-01-07
你把script標(biāo)簽放到</body>之前應(yīng)該就能起作用了
html從上向下執(zhí)行,執(zhí)行到getElementById的時(shí)候頁(yè)面上還沒(méi)有這個(gè)節(jié)點(diǎn),所以取不到