如果 url 查询字符串匹配，则设置选项 'selected'

Question

我有一个 select 框可以过滤页面上的数据库结果。每个选项的值都是查询字符串，以 ?然后是相应的 name/value 对特定选项 selected。像这样：

<select id="timeline-filter">
    <option value="log">Show All</option>
    <option value="?l=Previewed">Show Previewed</option>
    <option value="?l=Edited">Show Edited</option>
    <option value="?l=Downloaded">Show Downloaded</option>
    <option value="?l=Replaced">Show Replaced</option>
    <option value="?l=Deleted">Show Deleted</option>
</select>

例如，当用户 select 的选项如 "Show Previewed":

时，我需要做两件事

1) 我需要将页面重定向到 http://example.com/results?l=Previewed 2) 我需要将 "Show Previewed" 的选项设置为 selected，以便下拉列表指示这是当前过滤器。

我已经阅读了数十篇 jQuery 和 Javascript 文章，它们几乎达到了目标，但还不完全。我花了 3 个小时研究这个并尝试了各种方法，包括使用 Inspector 设置断点和观察变量，但我就是做不好。以下 HTML 和 jQuery 脚本完成了#1，但没有完成#2。

<select id="timeline-filter" onchange="this.options[this.selectedIndex].value && (window.location = this.options[this.selectedIndex].value);">
  <option value="log">Show All</option>
  <option value="?l=Previewed">Show Previewed</option>
  <option value="?l=Edited">Show Edited</option>
  <option value="?l=Downloaded">Show Downloaded</option>
  <option value="?l=Replaced">Show Replaced</option>
  <option value="?l=Deleted">Show Deleted</option>
</select>

<script>
  $(document).ready(function() {
    var queryString = window.location.href.slice(window.location.href.indexOf('?')).split('?');
    $("#timeline-filter > option").each(function() {
      if (this.value == queryString[0]) {
        this.selected = 'selected';
        /* ALTERNATE POSSIBILITY -- DOESN'T WORK EITHER
    $("#timeline-filter[value=this.value]").prop('selected',true)*/
      }
    });
  });
</script>

Answer 1

你差不多了，试试这个:-

$(document).ready(function() {
  var queryString = window.location.href.slice(window.location.href.indexOf('?'));
  $("#timeline-filter > option").each(function() {
    if (this.value == queryString) {
      this.selected = 'selected';
    }
  });
});

对于您的替代方案，试试这个：-

var queryString = window.location.href.slice(window.location.href.indexOf('?'));
$("#timeline-filter > option[value='" + queryString + "']").prop('selected', true)

下面测试

var href = "dfgdfgg.html?l=Replaced"

$(document).ready(function() {
  var queryString = href.slice(href.indexOf('?'));
  $("#timeline-filter > option").each(function() {
    if (this.value == queryString) {
      this.selected = 'selected';
    }
  });
});

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>

<select id="timeline-filter" onchange="this.options[this.selectedIndex].value && (window.location = this.options[this.selectedIndex].value);">
  <option value="log">Show All</option>
  <option value="?l=Previewed">Show Previewed</option>
  <option value="?l=Edited">Show Edited</option>
  <option value="?l=Downloaded">Show Downloaded</option>
  <option value="?l=Replaced">Show Replaced</option>
  <option value="?l=Deleted">Show Deleted</option>
</select>

如果 url 查询字符串匹配，则设置选项 'selected'

Set option 'selected' if url query string matches

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