使用Javascript在下拉菜單中選擇一個值

Question

$('select[name^="salesrep"] option[value="Bruce Jones"]').attr("selected","selected"); 

如何在JavaScript中編寫上面一段代碼？

Answer 1

您可以使用querySelector如下

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Answer 2

的JavaScript：

var mySelect = document.getElementById('salesrep'); 
 
for(var i, j = 0; i = mySelect.options[j]; j++) { 
 
    if(i.value == 'Bruce Jones') { 
 
     mySelect.selectedIndex = j; 
 
     break; 
 
    } 
 
}

<select name="salesrep" id="salesrep"> 
 
<option value="Bruce Jones">Bruce Jones</option> 
 
<option value="John Doo">John Doo</option> 
 
<option value="John Lee">John Lee</option> 
 
<option value="Jane Doo">Jane Doo</option> 
 
</select>