我有一个 JavaScript 代码，其中数据集被硬编码在一个变量中，就像这样 -
var dataset = [
{category: "Dept 1", measure: 0.30},
{category: "Dept 2", measure: 0.25},
{category: "Dept 4", measure: 0.15},
{category: "Dept 3", measure: 0.05},
{category: "Dept 5", measure: 0.18},
{category: "Dept 6", measure: 0.04},
{category: "Dept 7", measure: 0.03}
]
;
现在我想使用从 php 文件返回的 json 数据(通过 mysql 查询获取)。
执行此操作的有效方法是什么。 getJSON 在这种情况下工作得很好吗？
注意 - 我正在使用 d3.js 制作饼图，此数据集要求适用于该图表。
编辑 - 这是代码在建议更改后的样子 -
function dsPieChart(){
var width = 400,
height = 400,
outerRadius = Math.min(width, height) / 2,
innerRadius = outerRadius * .999,
// for animation
innerRadiusFinal = outerRadius * .5,
innerRadiusFinal3 = outerRadius* .45,
color = d3.scale.category20() //builtin range of colors
;
d3.json("data/mixchart.php", function(error, dataset) {
if (error) return console.warn(error);
else
{
var vis = d3.select("#pieChart")
.append("svg:svg") //create the SVG element inside the <body>
.data([dataset]) //associate our data with the document
.attr("width", width) //set the width and height of our visualization (these will be attributes of the <svg> tag
.attr("height", height)
.append("svg:g") //make a group to hold our pie chart
.attr("transform", "translate(" + outerRadius + "," + outerRadius + ")") //move the center of the pie chart from 0, 0 to radius, radius
;
var arc = d3.svg.arc() //this will create <path> elements for us using arc data
.outerRadius(outerRadius).innerRadius(innerRadius);
// for animation
var arcFinal = d3.svg.arc().innerRadius(innerRadiusFinal).outerRadius(outerRadius);
var arcFinal3 = d3.svg.arc().innerRadius(innerRadiusFinal3).outerRadius(outerRadius);
var pie = d3.layout.pie() //this will create arc data for us given a list of values
.value(function(d) { return d.measure; }); //we must tell it out to access the value of each element in our data array
var arcs = vis.selectAll("g.slice") //this selects all <g> elements with class slice (there aren't any yet)
.data(pie) //associate the generated pie data (an array of arcs, each having startAngle, endAngle and value properties)
.enter() //this will create <g> elements for every "extra" data element that should be associated with a selection. The result is creating a <g> for every object in the data array
.append("svg:g") //create a group to hold each slice (we will have a <path> and a <text> element associated with each slice)
.attr("class", "slice") //allow us to style things in the slices (like text)
.on("mouseover", mouseover)
.on("mouseout", mouseout)
.on("click", up)
;
arcs.append("svg:path")
.attr("fill", function(d, i) { return color(i); } ) //set the color for each slice to be chosen from the color function defined above
.attr("d", arc) //this creates the actual SVG path using the associated data (pie) with the arc drawing function
.append("svg:title") //mouseover title showing the figures
.text(function(d) { return d.data.category + ": " + formatAsPercentage(d.data.measure); });
d3.selectAll("g.slice").selectAll("path").transition()
.duration(750)
.delay(10)
.attr("d", arcFinal )
;
// Add a label to the larger arcs, translated to the arc centroid and rotated.
// source: http://bl.ocks.org/1305337#index.html
arcs.filter(function(d) { return d.endAngle - d.startAngle > .2; })
.append("svg:text")
.attr("dy", ".35em")
.attr("text-anchor", "middle")
.attr("transform", function(d) { return "translate(" + arcFinal.centroid(d) + ")rotate(" + angle(d) + ")"; })
//.text(function(d) { return formatAsPercentage(d.value); })
.text(function(d) { return d.data.category; })
;
// Computes the label angle of an arc, converting from radians to degrees.
function angle(d) {
var a = (d.startAngle + d.endAngle) * 90 / Math.PI - 90;
return a > 90 ? a - 180 : a;
}
// Pie chart title
vis.append("svg:text")
.attr("dy", ".35em")
.attr("text-anchor", "middle")
.text("Revenue Share 2012")
.attr("class","title")
;
}
});
function mouseover() {
d3.select(this).select("path").transition()
.duration(750)
//.attr("stroke","red")
//.attr("stroke-width", 1.5)
.attr("d", arcFinal3)
;
}
function mouseout() {
d3.select(this).select("path").transition()
.duration(750)
//.attr("stroke","blue")
//.attr("stroke-width", 1.5)
.attr("d", arcFinal)
;
}
function up(d, i) {
/* update bar chart when user selects piece of the pie chart */
//updateBarChart(dataset[i].category);
updateBarChart(d.data.category, color(i));
updateLineChart(d.data.category, color(i));
}
}
dsPieChart();编辑 2 -
<script type="text/javascript">
/*
################ FORMATS ##################
-------------------------------------------
*/
var formatAsPercentage = d3.format("%"),
formatAsPercentage1Dec = d3.format(".1%"),
formatAsInteger = d3.format(","),
fsec = d3.time.format("%S s"),
fmin = d3.time.format("%M m"),
fhou = d3.time.format("%H h"),
fwee = d3.time.format("%a"),
fdat = d3.time.format("%d d"),
fmon = d3.time.format("%b")
;
var width = 400,
height = 400,
outerRadius = Math.min(width, height) / 2,
innerRadius = outerRadius * .999,
// for animation
innerRadiusFinal = outerRadius * .5,
innerRadiusFinal3 = outerRadius* .45,
color = d3.scale.category20() //builtin range of colors
;
d3.json("data/mixchart.php", function(error,data) {
data.forEach(function(d) {
d.category =d.category;
d.measure = d.measure;
});
//if (err) return console.warn(err);
var vis = d3.select("#pieChart")
.append("svg:svg") //create the SVG element inside the <body>
.data(data) //associate our data with the document
.attr("width", width) //set the width and height of our visualization (these will be attributes of the <svg> tag
.attr("height", height)
.append("svg:g") //make a group to hold our pie chart
.attr("transform", "translate(" + outerRadius + "," + outerRadius + ")") //move the center of the pie chart from 0, 0 to radius, radius
;
var arc = d3.svg.arc() //this will create <path> elements for us using arc data
.outerRadius(outerRadius).innerRadius(innerRadius);
// for animation
var arcFinal = d3.svg.arc().innerRadius(innerRadiusFinal).outerRadius(outerRadius);
var arcFinal3 = d3.svg.arc().innerRadius(innerRadiusFinal3).outerRadius(outerRadius);
var pie = d3.layout.pie() //this will create arc data for us given a list of values
.value(function(d) { return d.measure; }); //we must tell it out to access the value of each element in our data array
var arcs = vis.selectAll("g.slice") //this selects all <g> elements with class slice (there aren't any yet)
.data(pie) //associate the generated pie data (an array of arcs, each having startAngle, endAngle and value properties)
.enter() //this will create <g> elements for every "extra" data element that should be associated with a selection. The result is creating a <g> for every object in the data array
.append("svg:g") //create a group to hold each slice (we will have a <path> and a <text> element associated with each slice)
.attr("class", "slice") //allow us to style things in the slices (like text)
.on("mouseover", mouseover)
.on("mouseout", mouseout)
.on("click", up)
;
arcs.append("svg:path")
.attr("fill", function(d, i) { return color(i); } ) //set the color for each slice to be chosen from the color function defined above
.attr("d", arc) //this creates the actual SVG path using the associated data (pie) with the arc drawing function
.append("svg:title") //mouseover title showing the figures
.text(function(d) { return d.data.category + ": " + formatAsPercentage(d.data.measure); });
d3.selectAll("g.slice").selectAll("path").transition()
.duration(750)
.delay(10)
.attr("d", arcFinal )
;
// Add a label to the larger arcs, translated to the arc centroid and rotated.
// source: http://bl.ocks.org/1305337#index.html
arcs.filter(function(d) { return d.endAngle - d.startAngle > .2; })
.append("svg:text")
.attr("dy", ".35em")
.attr("text-anchor", "middle")
.attr("transform", function(d) { return "translate(" + arcFinal.centroid(d) + ")rotate(" + angle(d) + ")"; })
//.text(function(d) { return formatAsPercentage(d.value); })
.text(function(d) { return d.data.category; })
;
// Computes the label angle of an arc, converting from radians to degrees.
function angle(d) {
var a = (d.startAngle + d.endAngle) * 90 / Math.PI - 90;
return a > 90 ? a - 180 : a;
}
// Pie chart title
vis.append("svg:text")
.attr("dy", ".35em")
.attr("text-anchor", "middle")
.text("Revenue Share 2012")
.attr("class","title")
;
function mouseover() {
d3.select(this).select("path").transition()
.duration(750)
//.attr("stroke","red")
//.attr("stroke-width", 1.5)
.attr("d", arcFinal3)
;
}
function mouseout() {
d3.select(this).select("path").transition()
.duration(750)
//.attr("stroke","blue")
//.attr("stroke-width", 1.5)
.attr("d", arcFinal)
;
}
function up(d, i) {
/* update bar chart when user selects piece of the pie chart */
//updateBarChart(dataset[i].category);
updateBarChart(d.data.category, color(i));
updateLineChart(d.data.category, color(i));
}
</script>最佳答案
var dataset = [];
$.getJSON("your_php_file", function(result){
dataset = result;
});
这会起作用，但请记住，您的 php 文件只返回 json...剩下的，您可以使用这些选项。
关于javascript - 用从 php 文件返回的 json 值替换固定的 json 变量，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/36400615/