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我們先看看錯誤的例子
Html代碼
複製代碼 代碼如下:
<body>
<input id="certid" type="text" value="123456" >
<input id="btn" type="button" value="button" onclick="">
</body>
Javascript代碼
複製代碼 代碼如下:
<script>
function show(value)
{
alert(value);
}
btn.onclick = show(certid.value);
<script>
以上代碼執行起來是有錯誤的,因為show(certid.value)這句,直接就執行了show方法,而沒有正確把這個方法對象賦給btn.onclick事件.
如果我們改成這樣
複製代碼 代碼如下:
btn.onclick = show;
參數又無法傳遞.
所以正確的代碼應該這樣寫,我們加一個參數以看得更明白一些:
Html代碼
複製代碼 代碼如下:
<body>
<input id="certid" type="text" value="123456" >
<input id="btn" type="button" value="button" onclick="">
</body>
Javascript代碼
複製代碼 代碼如下:
<script>
function show(value1,value2)
{
alert(value1+","+value2);
}
var i = 10;
btn.onclick = function(){
show(certid.value,i);
};
<script>
這樣就實現了動態給onclick事件控制代碼賦值,並支援參數的傳遞.
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