Javascript 仅在单击下拉列表中的项目时显示列表框
我的页面上有一个下拉列表和一个列表框，两者都是可见的，但我只希望我的下拉列表是可见的，当我从下拉列表中选择任何项目时，列表框应该是可见的。否则它应该是隐藏的。请帮助！！这是我的htmlJavascript 仅在单击下拉列表中的项目时显示列表框,javascript,jquery,html,Javascript,Jquery,Html,我的页面上有一个下拉列表和一个列表框，两者都是可见的，但我只希望我的下拉列表是可见的，当我从下拉列表中选择任何项目时，列表框应该是可见的。否则它应该是隐藏的。请帮助！！这是我的html <!doctype html> <html> <head> <meta charset="UTF-8"> <meta content="utf-8" http-equiv="encoding"> <title>D3&l
<!doctype html>
<html>
<head>
<meta charset="UTF-8">
<meta content="utf-8" http-equiv="encoding">
<title>D3</title>
<!-- <link rel="stylesheet" type="text/css" href="mystyle1.css" /> -->
<style>
body {
color: #000;
}
.axis {
font: 10px sans-serif;
}
.axis path,
.axis line {
fill: none;
stroke: #000;
shape-rendering: crispEdges;
}
.bar {
fill: steelblue;
}
.bar:hover {
fill: brown;
}
</style>
<script type="text/javascript" src="http://mbostock.github.com/d3/d3.js"></script>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.12.2/jquery.min.js"></script>
<script src="123.js" type="text/javascript"></script>
</head>
<script src="http://d3js.org/d3.v3.min.js"></script>
<body>
<div id="chart"></div>
<div align="center">
From : <input type="date" name="field1" id="field1" /> To : <input type="date" name="field2" id="field2" /><br /><br />
<input type="button" onclick="render(true)" value="Submit" />
</div>
<script>
var jsonURL = 'myData.json';
var myData = [];
var margin = {
top: 20,
right: 0,
bottom: 80,
left: 40
};
var width = 500 - margin.left - margin.right;
var height = 300 - margin.top - margin.bottom;
var xScale = d3.scale.ordinal().rangeRoundBands([0, width], .1);
var yScale = d3.scale.linear().range([height, 0]);
var hAxis = d3.svg.axis().scale(xScale).orient('bottom').tickFormat(d3.time.format("%Y-%m-%d"));
var vAxis = d3.svg.axis().scale(yScale).orient('left');
var tooltip = d3.select('body').append('div')
.style('position', 'absolute')
.style('background', '#f4f4f4')
.style('padding', '5 15px')
.style('border', '1px #333 solid')
.style('border-radius', '5px')
.style('opacity', 'o');
function getDates() {
return [document.getElementById('field1').value, document.getElementById('field2').value];
}
function render(filterByDates) {
d3.select('svg').remove();
if (filterByDates) {
var date1 = new Date(document.getElementById('field1').value);
var date2 = new Date(document.getElementById('field2').value);
myData = myData.filter(function (d) {
return d.date >= date1 && d.date <= date2;
});
}
xScale.domain(myData.map(function (d) {
return d.date;
}));
yScale.domain([0, d3.max(myData, function (d) {
return d.value;
})]);
var svg = d3.select('#chart').append('svg')
.attr("width", width + margin.left + margin.right)
.attr("height", height + margin.top + margin.bottom)
.append("g")
.attr("transform", "translate(" + margin.left + "," + margin.top + ")");
svg
.append('g')
.attr("class", "x axis")
.attr("transform", "translate(0," + height + ")")
.call(hAxis)
.selectAll("text")
.style("text-anchor", "end")
.attr("dx", "-.8em")
.attr("dy", "-.55em")
.attr("transform", "rotate(-90)");
svg
.append('g')
.attr("class", "y axis")
// .attr('transform', 'translate(35,' + (height - 25) + ')')
.call(vAxis)
svg
.selectAll(".bar")
.data(myData)
.enter().append("rect")
.attr("class", "bar")
.style("fill", "steelblue")
.attr("x", function (d) {
return xScale(d.date);
})
.attr("width", xScale.rangeBand())
.attr("y", function (d) {
return yScale(d.value);
})
.attr("height", function (d) {
return height - yScale(d.value);
})
.on('mouseover', function (d) {
tooltip.transition()
.style('opacity', 1)
tooltip.html(d.value)
.style('left', (d3.event.pageX) + 'px')
.style('top', (d3.event.pagey) + 'px')
d3.select(this).style('opacity', 0.5)
})
.on('mouseout', function (d) {
tooltip.transition()
.style('opacity', 0)
d3.select(this).style('opacity', 1)
});
}
d3.json(jsonURL, function (data) {
myData = data;
myData.forEach(function (d) {
d.date = new Date(d.date);
d.name = +d.name;
});
render(false);
});
</script>
<label> List of Tables : </label><br>
<form name="myform" id="myForm">
<div style="height: 30px; width: 50px;">
<select id="dropdown1"></select>
</div>
<style>
#listbox {
position: relative;
}
</style>
<div style="margin-left: 150px; margin-top: -30px; height: auto;">
<select id="listbox" , multiple></select>
</div>
<br>
</form>
</html>
$(document).ready(function () {
$.ajax({
url: "mydata.json",
dataType: "json",
success: function (obj) {
var jsObject = obj;
var usedNames = [];
$('<option>', {
text: 'Select your Option',
value: '',
selected: 'selected',
disabled: 'disabled',
location: 'fixed'
}).appendTo('#dropdown1')
$.each(obj, function (key, value) {
if (usedNames.indexOf(value.name) == -1) {
$("#dropdown1").append("<option value=" + key + ">" + value.name + "</option>");
usedNames.push(value.name);
}
/* $('<option>', {
text: 'Select your Option',
value: '',
selected: 'selected',
disabled: 'disabled'
}).appendTo('#dropdown1');
*/
$('#dropdown1').change(function () {
$('#listbox').empty();
$('<option>', {
text: 'Select your List Option',
value: '',
selected: 'selected',
disabled: 'disabled'
}).appendTo('#listbox');
var selection = $('#dropdown1 :selected').text();
// var selection = $('#dropdown1 :selected').text();
$.each(jsObject, function (index, value) {
if (value['name'] == selection) {
var optionHtml = '';
for (var i = 1; i <= 20; i++) {
var attr = 'attr' + ('000' + i).substr(-3);
optionHtml += '<option value="' + attr + '">' + value[attr] + '</option>';
}
$("#listbox").css("width", "500px")
$("#listbox").css("height", "300px")
$('#listbox').append(optionHtml);
return false;
}
});
});
});
}
});
});
以下内容将对您有所帮助 $'dropdown1'.changefunction{ $'listbox'。切换this.value！=； }; 列表框{ 显示：无； } 选择 选择1 选择2 选择1