<form name=form1>
<select name=com_idA onchange="document.form1.com_idB.value=''">
<option value="">-PleaseSelectA-</option>
<option value="A1">A1</option>
<option value="A2">A2</option>
</select>
<select name=com_idB onchange="document.form1.com_idA.value=''">
<option value="">-PleaseSelectB-</option>
<option value="B1">B1</option>
<option value="B2">B2</option>
</select>
</form>
<select name=com_idA onchange="document.form1.com_idB.value=''">
<option value="">-PleaseSelectA-</option>
<option value="A1">A1</option>
<option value="A2">A2</option>
</select>
<select name=com_idB onchange="document.form1.com_idA.value=''">
<option value="">-PleaseSelectB-</option>
<option value="B1">B1</option>
<option value="B2">B2</option>
</select>
</form>
解决方案 »
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