Question

页面上有3个下拉菜单。在用户选择后，它将更改图像和标题。以下是onLoad功能的一部分。但是，我正在寻找一种解决方案来组合这3个基本相同的功能。

我尝试了将变量作为数组索引的不同方法，例如myChoice [x] .onchange with for（x in array）等，但不能使它工作。

myChoice是一个Select元素数组，从中提取图像和标题的必要值。 myThumb是一个Image元素数组。 myDesc是用于标题的Span元素数组。

我真的很感激良好的投入。谢谢！

myChoice [0] = .onchange函数（）
{
JPG文件= THIS.VALUE;
filechar = jpgfile.length-3;
shortfile = jpgfile.substr（filechar，3）;
myThumb [0]的.src = BP + '松露' + shortfile + 'JPG';
captext = shortfile.substr（2,1）;
myDesc [0] = .innerHTML字幕[captext];
}

myChoice [1] .onchange =函数（）
{
JPG文件= THIS.VALUE;
filechar = jpgfile.length-3;
shortfile = jpgfile.substr（filechar，3）;
myThumb [1]的.src = BP + '松露' + shortfile + 'JPG';
captext = shortfile.substr（2,1）;
myDesc [1] .innerHTML =字幕[captext];
}

myChoice [2] = .onchange（）函数 {
JPG文件= THIS.VALUE;
filechar = jpgfile.length-3;
shortfile = jpgfile.substr（filechar，3）;
myThumb [2]的.src = BP + '松露' + shortfile + 'JPG';
captext = shortfile.substr（2,1）;
myDesc [2] .innerHTML =字幕[captext]; }

包含建议功能的完整代码

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN"
"http://www.w3.org/TR/html4/strict.dtd">

<html>

<head>

<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<style type="text/css">
img.choicePic {
display:block;
}
h1 {
font-family:arial, Verdana, tahoma;
font-size:17pt;
text-align:center;
display:block;
}
#caption0, #caption1, #caption2 {
font-family:arial, Verdana, tahoma;
font-size:7pt;
text-align:left;
display:block;
}
</style>
<script type="text/javascript">

function setPicCap() {

var caption=['Select your chocolate',
'Flavors from India: nutmeg and subtle spices, in milk chocolate, dusted with cinnamon. ',
'Caribbean flavors of rum and butter mingle in a creamy center, dipped in dark chocolate. ',
'Dark chocolate truffle center, dipped in dark chocolate with white chocolate stripes. ',
]; // This will be your images description




var bp='images/store/', //base url of your images
imgnum=3; //Number of your images. This should match on your comboboxes options.

var myThumb=new Array(3), myDesc=new Array(3), myChoice=new Array(3);

for (i=0; i<imgnum; i++) {

numChoice=i.toString();
imgChoice="thumb"+numChoice;
capChoice="caption"+numChoice;
selectChoice="selection"+numChoice;

imgChoice=document.getElementById(imgChoice); //Image element. Use .src to view specific.
myThumb[i]=imgChoice;


capChoice=document.getElementById(capChoice); //Span element. Place holder. No value.
myDesc[i]=capChoice;

selectChoice=document.getElementById(selectChoice); //Select element. Use innerHTML to view specific.
myChoice[i]=selectChoice;

}

function updateThumb(index, jpgfile){
shortfile = jpgfile.substr(jpgfile.length - 3,3);
myThumb[index].src = bp + 'truffle' + shortfile + '.jpg';
captext = shortfile.substr(2,1);
myDesc[index].innerHTML = caption[captext];
}

for(var j = 0; j < myChoice.length; j++){
var idx = j;
myChoice.onchange = function(){
updateThumb(idx, this.value);
}
}
}


</script>
</head>
<body onLoad="setPicCap()">
<center>
<h1>Build Your Computer Test Script</h1>
</center>
<table width="800" align="center">
<tr>
<td><img src="images/store/select_a_chocolate.png" alt="Mukilteo Choclate Truffle" border="0" id="thumb0" class="choicePic"></td>
<td><select id="selection0" name="truffle">
<option value="0" selected >Select Your Chocolate</option>
<option value="Square0: BANGALORE SPICE Item 001|BANGALORE SPICE Item 001">BANGALORE SPICE Item 001</option>
<option value="Square0: BUTTERED RUM Item 002|BUTTERED RUM Item 002">BUTTERED RUM Item 002</option>
<option value="Square0: CLASSIC DARK CHOCOLATE Item 003|CLASSIC DARK CHOCOLATE Item 003">CLASSIC DARK CHOCOLATE Item 003</option>
</select>
<br></td>
</tr>
<tr>
<td colspan="2"><span id="caption0"></span></td>
</tr>
</table>
<br>
<br>
<br>
<table width="800" align="center">
<tr>
<td><img src="images/store/select_a_chocolate.gif" alt="Mukilteo Choclate Truffle" border="0" id="thumb1" class="choicePic"></td>
<td><select id="selection1" name="truffle">
<option value="0" selected >Select Your Chocolate</option>
<option value="Square1: BANGALORE SPICE Item 001|BANGALORE SPICE Item 001">BANGALORE SPICE Item 001</option>
<option value="Square1: BUTTERED RUM Item 002|BUTTERED RUM Item 002">BUTTERED RUM Item 002</option>
<option value="Square1: CLASSIC DARK CHOCOLATE Item 003|CLASSIC DARK CHOCOLATE Item 003">CLASSIC DARK CHOCOLATE Item 003</option>
</select>
<br></td>
</tr>
<tr>
<td colspan="2"><span id="caption1"></span></td>
</tr>
</table>
<br>
<br>
<br>
<table width="800" align="center">
<tr>
<td><img src="images/store/select_a_chocolate.jpg" alt="Mukilteo Choclate Truffle" border="0" id="thumb2" class="choicePic"></td>
<td><select id="selection2" name="truffle">
<option value="0" selected >Select Your Chocolate</option>
<option value="Square2: BANGALORE SPICE Item 001|BANGALORE SPICE Item 001">BANGALORE SPICE Item 001</option>
<option value="Square2: BUTTERED RUM Item 002|BUTTERED RUM Item 002">BUTTERED RUM Item 002</option>
<option value="Square2: CLASSIC DARK CHOCOLATE Item 003|CLASSIC DARK CHOCOLATE Item 003">CLASSIC DARK CHOCOLATE Item 003</option>
</select>
<br></td>
</tr>
<tr>
<td colspan="2"><span id="caption2"></span></td>
</tr>
</table>
</body>
</html>

Answer 1

function updateThumb(index, jpgfile){
    shortfile = jpgfile.substr(jpgfile.length - 3,3);
    myThumb[index].src = bp + 'truffle' + shortfile + '.jpg';
    captext = shortfile.substr(2,1);
    myDesc[index].innerHTML = caption[captext];
}

for(var i = 0; i < myChoice.length; i++){
    var idx = i;
    myChoice.onchange = function(){
        updateThumb(idx, this.value);
    }
}

Answer 2

你走了：

function setPicCap() {
function a(a, d) {
    shortfile = d.substr(d.length - 3, 3), e[a].src = c + "truffle" + shortfile + ".jpg", captext = shortfile.substr(2, 1), f[a].innerHTML = b[captext]
}
var b = ["Select your chocolate", "Flavors from India: nutmeg and subtle spices, in milk chocolate, dusted with cinnamon. ", "Caribbean flavors of rum and butter mingle in a creamy center, dipped in dark chocolate. ", "Dark chocolate truffle center, dipped in dark chocolate with white chocolate stripes. "],
    c = "images/store/",
    d = 3,
    e = Array(3),
    f = Array(3),
    g = Array(3);
for (i = 0; d > i; i++) numChoice = i + "", imgChoice = "thumb" + numChoice, capChoice = "caption" + numChoice, selectChoice = "selection" + numChoice, imgChoice = document.getElementById(imgChoice), e[i] = imgChoice, capChoice = document.getElementById(capChoice), f[i] = capChoice, selectChoice = document.getElementById(selectChoice), g[i] = selectChoice;
for (var h = 0; g.length > h; h++) {
    var j = h;
    g.onchange = function () {
        a(j, this.value)
    }
}
}

如何简化数组onchange函数

2 个答案: