Javascript - 基于动态填充下拉菜单的转到 url

Question

我创建了一个条件表单，单击提交后需要定向到特定的产品页面。这段代码可以做到这一点吗？我无法弄清楚如何将数组值链接到 URL 变量。

Here's the JSFiddle

a=new Array("V1-1: 1/4-4 900-4500#", "V1-1 Light-Weight Compact Solution", "V1-2: 1/2-36 150-600#","V1-3: 1/2-2, 150-600#","V1-4: 4-36 900-4500#");
b=new Array('NexTech® R Series Valves','NexTech® E Series Valves','TrunTech® Valves', 'PulseJet Valves');
c=new Array('Coking Isolation Valves','Coking Switch Valves');
d=new Array('Three-Way Valves','Four-Way Valves');
e=new Array('IsoTech®');
f=new Array('Xactrol® Mark I Valves', 'Xactrol® Mark II Valves', 'Xactrol® Mark III Valves');
g=new Array('PulseJet Valves','Ecopack®');
h=new Array('AbrasoCheck® Slurry Check Valves', 'AbrasoTech® Slurry Ball Valves');
i=new Array('Electronic Relief Valves');
j=new Array('ValvXpress® Automated Valve Packages');
k=new Array('Acid Injection Valves');
l=new Array('Double Block-and-Bleed Valves');
m=new Array('Turbine Bypass System');
n=new Array('Check Valves');
o=new Array('ValvXpress®','EcoPack®','ValvPerformance Testing®','Slurry Valves','Acid Injection Valves','Double Block-and-bleed Valves','Rhinoite® Hardfacing','Switch Valves','HVOF RiTech®','Cryogenic Valves');

populateSelect();

$(function() {

      $('#cat').change(function(){
        populateSelect();
    });

});


function populateSelect(){
    cat=$('#cat').val();
    $('#item').html('');


    if(cat=='a'){
        a.forEach(function(t) { 
            $('#item').append('<option>'+t+'</option>');
        });
    }

    if(cat=='b'){
        b.forEach(function(t) {
            $('#item').append('<option>'+t+'</option>');
        });
    }

    if(cat=='c'){
        c.forEach(function(t) {
            $('#item').append('<option>'+t+'</option>');
        });
    }

    if(cat=='d'){
        d.forEach(function(t) {
            $('#item').append('<option>'+t+'</option>');
        });
    }

    if(cat=='e'){
        e.forEach(function(t) {
            $('#item').append('<option>'+t+'</option>');
        });
    }

    if(cat=='f'){
        f.forEach(function(t) {
            $('#item').append('<option>'+t+'</option>');
        });
    }

    if(cat=='g'){
        g.forEach(function(t) {
            $('#item').append('<option>'+t+'</option>');
        });
    }

    if(cat=='h'){
        h.forEach(function(t) {
            $('#item').append('<option>'+t+'</option>');
        });
    }


    if(cat=='i'){
        i.forEach(function(t) {
            $('#item').append('<option>'+t+'</option>');
        });
    }

    if(cat=='j'){
        j.forEach(function(t) {
            $('#item').append('<option>'+t+'</option>');
        });
    }

    if(cat=='k'){
        k.forEach(function(t) {
            $('#item').append('<option>'+t+'</option>');
        });
    }

    if(cat=='l'){
        l.forEach(function(t) {
            $('#item').append('<option>'+t+'</option>');
        });
    }

    if(cat=='m'){
       m.forEach(function(t) {
            $('#item').append('<option>'+t+'</option>');
        });
    }

    if(cat=='n'){
        n.forEach(function(t) {
            $('#item').append('<option>'+t+'</option>');
        });
    }

    if(cat=='o'){
        o.forEach(function(t) {
            $('#item').append('<option>'+t+'</option>');
        });
    }





} 

Answer 1

首先，您违反了DRY principle 。不要为每组产品设置单独的变量，而是将每个产品存储在某种字典结构(例如对象)中。

这将是我的第一次修订。

var dict = {
    a: ["V1-1: 1/4-4 900-4500#", "V1-1 Light-Weight Compact Solution", "V1-2: 1/2-36 150-600#","V1-3: 1/2-2, 150-600#","V1-4: 4-36 900-4500#"],
    b: ['NexTech® R Series Valves','NexTech® E Series Valves','TrunTech® Valves', 'PulseJet Valves'],
    c: ['Coking Isolation Valves','Coking Switch Valves'],
    d: ['Three-Way Valves','Four-Way Valves'],
    e: ['IsoTech®'],
    f: ['Xactrol® Mark I Valves', 'Xactrol® Mark II Valves', 'Xactrol® Mark III Valves'],
    g: ['PulseJet Valves','Ecopack®'],
    h: ['AbrasoCheck® Slurry Check Valves', 'AbrasoTech® Slurry Ball Valves'],
    i: ['Electronic Relief Valves'],
    j: ['ValvXpress® Automated Valve Packages'],
    k: ['Acid Injection Valves'],
    l: ['Double Block-and-Bleed Valves'],
    m: ['Turbine Bypass System'],
    n: ['Check Valves'],
    o: ['ValvXpress®','EcoPack®','ValvPerformance Testing®','Slurry Valves','Acid Injection Valves','Double Block-and-bleed Valves','Rhinoite® Hardfacing','Switch Valves','HVOF RiTech®','Cryogenic Valves']
};

$(function() {
    // attach an 'change' event handler
    // THEN trigger the event handler to call the function from the start
    $('#cat').change(populateSelect).trigger('change');
});

function populateSelect() {
    // this refers to the current element
    // get the selected value
    var cat = this.value;
    // always a good idea to cache your element that you will be re-using (maybe move it outside the function too)
    var items = $('#item');

    items.html('');
    // check if there are products associated with the selected value
    if (dict.hasOwnProperty(cat)) {
        // show products
        dict[cat].forEach(function(product) { 
            items.append('<option>' + product + '</option>');
        });
    }
}

现在，就您的实际问题而言。我们可以修改数组，使其也包含 url。为了简单起见，您可以使用数组的数组，例如

a: [["V1-1: 1/4-4 900-4500#", "url"], ["V1-1 Light-Weight Compact Solution", "url"], ...]

或对象数组以提高可读性，例如

a: [{ name: "V1-1: 1/4-4 900-4500#", url: "url" }, { name: "V1-1 Light-Weight Compact Solution", url: "url"}, ...]

这是我使用对象数组的第二次修订。 (我缩短了字典只是为了显示说明)。

var dict = {
    a: [
        { 
            name: "V1-1: 1/4-4 900-4500#",
            url: "http://www.bing.com"
        },
        {
            name: "V1-1 Light-Weight Compact Solution", 
            url: "http://www.google.com"
        },
        {
            name: "V1-2: 1/2-36 150-600#",
            url: "http://www.yahoo.com"
        },
    ],
    b: [
        {
            name: 'NexTech® R Series Valves',
            url: 'http://www.nike.com'
        },
        {
            name: 'NexTech® E Series Valves',
            url: 'http://www.walmart.com'
        }
    ],
    c: [{
        name: 'Coking Isolation Valves',
        url: 'http://www.adidas.com'
    }],
};

$(function() {
    // cache element so that you don't re-search the DOM multiple times
    var $items = $('#item');

    $('#cat').change(populateSelect).trigger('change');
    $('#goto').click(redirectToURL);

    // place the functions within the document.ready so that they have access to the cached elements
    function populateSelect() {
        $items.html('');
        if (dict.hasOwnProperty(this.value)) {
            dict[this.value].forEach(function(product) {
                // you can store the URL in HTML5-data attribute to use it later
                $items.append('<option data-url="' + product.url + '">' + product.name +'</option>');
            });
        }
    }

    function redirectToURL() {
        // get the URL from the selected option's data-url and redirect to it
        window.location.href = $items.find(':selected').data('url');
    }
});

从技术上讲，您不是在“提交”表单，而只是“重定向”——因此我不会使用提交按钮，而只是使用普通按钮。

<input type="button" id="goto" value="submit">

下面是 demo最终修订版。你必须修复字典。