如果用語句確定在xmlhttp.open上調用哪個url GET

Question

尋找一種方法來根據選擇來編寫if語句，這將決定xmlhttp.open("GET"使用的url。例如1,2,3選擇"test2.php?q=" + str，4選擇"test3.php?q=" + str，5選定"test4.php?q=" + str

<form style="width: 210px"> 
    <select name="bookings" onchange="showbookings(this.value)"> 
     <option value="">Select Booking Types To See:</option> 
     <option value="1">All Booking</option> 
     <option value="2">Open Bookings</option> 
     <option value="3">Closed Bookings</option> 
     <option value="4">Potential Bookings</option> 
     <option value="5">Create Bookings</option> 
    </select> 
</form> 
<div id="txtBookings"></div> 


function showbookings(str) { 
if (str === "") { 
    document.getElementById("txtBookings").innerHTML = ""; 
    return; 
} 
if (window.XMLHttpRequest) { // code for IE7+, Firefox, Chrome, Opera, Safari 
    xmlhttp = new XMLHttpRequest(); 
} else { // code for IE6, IE5 
    xmlhttp = new ActiveXObject("Microsoft.XMLHTTP"); 
} 
xmlhttp.onreadystatechange = function() { 
    if (xmlhttp.readyState == 4 && xmlhttp.status == 200) { 
     document.getElementById("txtBookings").innerHTML = xmlhttp.responseText; 

    } 
}; 
xmlhttp.open("GET", "test2.php?q=" + str, true); 
xmlhttp.send(); 
} 

Answer 1

var url = ''; 
if (str == '5') 
    url = 'test4.php?q='+str; 
else if (str == '4') 
    url = 'test3.php?q='+str; 
else if (str != '') 
    url = 'test2.php?q='+str; 
if (url) { 
    xmlhttp.open("GET", url, true); 
    xmlhttp.send(); 
} 

Answer 2

你可以嘗試這樣的事情

function showbookings(str) { 
    if (!str) { 
     return; 
    } 
    var num = str > 3 ? str-1 : 2; 
    xmlhttp = window.XMLHttpRequest ? new XMLHttpRequest() : new ActiveXObject("Microsoft.XMLHTTP"); 
    xmlhttp.onreadystatechange = function() { 
     // ... 
    } 

    xmlhttp.open("GET", "test"+num+".php?q=" + str, true); 
    xmlhttp.send(); 
}