JavaScript功能有时失败onchange

Question

所以我有这个网页代码，它在Firefox中工作（有点），但只有选择在IE8中工作。为了使它在Firefox中工作，警报（null）必须在那里，否则将不会转到href当myloc == "MySrch"。我没有收到任何反馈错误，这真是令人困惑。

SqlStr = "Select DISTINCT Unit From Employee Where PhoneBook = 1 Order by Unit;" 
Set UniNme = Connection.Execute(SqlStr) 
Response.Write "<select id='Unit' onChange='Change(this.id)'>" 
Response.Write "<option value=''>Choose Unit</option><br>" 
Response.Write "<option value='Everyone'>Everyone</option><br>" 
Do While Not UniNme.EOF 
Response.Write "<option value='"&UniNme("Unit")&"'>"&UniNme("Unit")&"</option><br>" 
UniNme.MoveNext 
Loop 
Response.Write "</select><br>" 

Response.Write "Name Search: <input type='text' id='MySrch' onChange='Change(this.id)'>" 

JavaScript函数是

function Change(myloc) { 
if (myloc == "Unit") { 
var myindex = document.getElementById(myloc).selectedIndex; 
myvalue = document.getElementsByTagName("option")[myindex].value; 
} else { 
var myvalue = document.getElementById(myloc).value; 
} 

document.cookie = "Temp1="+escape(myloc); 
document.cookie = "Temp2="+escape(myvalue); 

document.location.href="AEmployees.asp?action=Change"; 

alert(null); 
} 

Answer 1

看一看myvalue的变量的范围。它在这里

else { 
var myvalue = document.getElementById(myloc).value; 
} 

当地的知名度，可能不会引起问题，但它是有潜在危险的代码