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javascript限制輸入的只能是數字，判斷event.keyCode的值，並將它限定只能為數字，如果不是數字，則返回錯誤，如果是數字，則繼續。<br />我先介紹驗證javascript是否是數字另一種方式，通過下面的函數來實現：<br />function isNumber(oNum)<br /> {<br /> if(!oNum) return false;<br /> var strP=/^/d+(/./d+)?$/;<br /> if(!strP.test(oNum)) return false;<br /> try{<br /> if(parseFloat(oNum)!=oNum) return false;<br /> }<br /> catch(ex)<br /> {<br /> return false;<br /> }<br /> return true;<br /> }<br />這段javascript代碼很簡潔，大家可以看下。<br /><mce:script language=javascript><!--<br />function onlyNum()<br />{<br />if(!((event.keyCode>=48&&event.keyCode<=57)||(event.keyCode>=96&&event.keyCode<=105)))<br />//考慮小鍵盤上的數字鍵<br />event.returnvalue=false;<br />}<br />// --></mce:script><br /><input onkeydown="onlyNum();"><br />下面還有一種比較笨的方法，大家也可以看下，學習嘛<br />下次貼個用正則驗證數位<br /><mce:script language="javascript"><!--</p><p>function CheckMyForm()<br />{<br />var txt = myform.mytext.value;<br />if(checknumber(txt))<br />{<br />alert("只允許輸入數字！");<br />return false;<br />}<br />return true;<br />}<br />function checknumber(String)<br />{<br />var Letters = "1234567890";<br />var i;<br />var c;<br />for( i = 0; i < String.length; i ++ )<br />{<br />c = String.charAt( i );<br />if (Letters.indexOf( c ) ==-1)<br />{<br />return true;<br />}<br />}<br />return false;<br />}<br />// --></mce:script><br /><body><br /><form name="myform" onSubmit="return CheckMyForm()"><br /><input type="text" name="mytext"><br /><input type="submit" name="mysubmit"><br /></form><br /></body><br />最簡單的javascript驗證是否不是數位代碼如下：<br /><input type='TEXT' onKeyPress="if(event.keyCode==13){if(isNaN(this.value))alert('不是數值')};"><br />
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