Question

我目前正在尝试根据用户使用JavaScript在查询表单上输入的输入构建API的URL。文本字段的输入保存在变量中，该变量进一步联合在一起作为最终URL。然而，并非所有输入字段都将一直使用。

我想知道如果它的值为空，你如何忽略该特定变量。

正如我解释的那样，我有一组输入字段：

<input id="whoValue"  type="text" value=""   placeholder="Who">    
<input id="whenStart" type="text" value="" placeholder="Start Date">
<input id="whenEnd" type="text" value="" placeholder="End Date">
<input id="whatValue"  type="text" value="" placeholder="What">
<button id="searchBtn">Search</button></br>
<input id="result" type="text" value="" placeholder="Resulting URL">

然后按下该按钮时，即使内容为空，JavaScript也会加入输入字段。

$('#searchBtn').click(function () {

    var url = 'http://particularURLof/';
    var who = "…WHO" + $('#whoValue').val();
    var what = "…WHAT"+ $('#whatValue').val();
    var when = "…YEAR[" + $('#whenStart').val() + "+TO+" + $('#whenEnd').val() + "]";
    var moreUrl = '…url End';

    var resultUrl = url + who + what + when + moreUrl;
    $("#result").val(resultUrl);

});

因此，如上所述，我正在尝试仅使用变量构建resultUrl 保持值 输入字段< /强>

以下是我所拥有的JSFiddle 。

Answer 1

简短，如果不喜欢：

var result = if_this_is_true ? true : false;

为您提供代码示例

$('#searchBtn').click(function () {

    var url     = 'http://particularURLof/';
    var who     = $('#whoValue').val().length > 0   ? "…WHO" + $('#whoValue').val() : '';
    var what    = $('#whatValue').val().length > 0  ? "…WHAT"+ $('#whatValue').val() : '';
    var moreUrl = '…url End';

    var resultUrl = who + what + moreUrl;
    $("#result").val(resultUrl);

});

http://jsfiddle.net/n1jtrpmv/1/

Answer 2

$（'＃searchBtn'）。click（function（）{

var url = 'http://particularURLof/';
var who = $('#whoValue').val();
var what = $('#whatValue').val();
var whenStart = $('#whenStart').val();
var whatEnd = $('#whenEnd').val(); 
var moreUrl = "endOfUrl";

if( (who != '') && (what != '') && (whenStart != '') && (whenEnd != '') ) {
   var resultUrl = url + who + what + whenStart + whenEnd + moreUrl;
} 
else if( (who == '') && (what != '') && (whenStart != '') && (whenEnd != '') ) {
   var resultUrl = url + what + whenStart + whenEnd + moreUrl;
} 
else if( (who != '') && (what == '') && (whenStart != '') && (whenEnd != '') ) {
   var resultUrl = url + who + whenStart + whenEnd + moreUrl;
}
else if( (who != '') && (what != '') && ((whenStart == '') || (whenEnd == '')) ) {
   var resultUrl = url + who + what + moreUrl;
}

$("#result").val(resultUrl);

}）;

如果输入字段为空，则删除或忽略变量

2 个答案: