[問題] 搞不懂javascript的邏輯...
<script language = "javascript">
function a(x){
for(i=1;i<=2;i++)
{
var colname = "\"col"+i+"\""
y=document.getElementById(colname)
var msg = "COLNAME : "+colname+" i: "+i+" Y: "+y;
alert(msg)
}
}
</script>
<select id = "col1" onchange = "a(this);">
<option>1</option>
<option>2</option>
<option>3</option>
</select>
<select id = "col2" onchange = "a(this);">
<option>1</option>
<option>2</option>
<option>3</option>
</select>
紅色字部份不管有沒有加結果都一樣
alert 結果為 ：
COLNAME : "col1" i: 1 Y: null
COLNAME : "col2" i: 2 Y: null
為什麼 y 會是null 呢?
※ 編輯: averywu 來自: 59.124.142.152 (12/01 01:08)
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