来自一个页面的多个ajax请求+如何操作+最佳实践

时间:2018-03-28 03:19:28

标签: php ajax google-visualization

我正在处理谷歌图表,我已经有一个基本的设置。

它目前所做的是连接到数据库并根据1个查询返回数据集。我想知道的是,如果我想用不同的查询绘制更多图表到数据库我该怎么做?或者最佳做法是什么?

例如,一个查询已经有一个连接,如何添加另一个查询,然后根据返回的内容绘制图表?

我理解这可能是一个广泛的问题,但也许有人可以告诉我如何从数据库中返回不同的查询/数据集?

这是我的代码:

 $(document).ready(function(){

    console.log("hello world")
    //alert("result")

    $.ajax({
        url:"data.php",
        dataType : "json",
        success : function(result) {
            google.charts.load('current', {
                'packages':['corechart','bar']
            });
            google.charts.setOnLoadCallback(function() {
                console.log(result[0]["name"])
                drawChart(result);                  
            });
        }
    }); 

    //add a 2nd call - will need a 2nd draw charts to draw the different dataset assuming it will be different
    //                  - will need a 2nd data.php as the query will be different on the dataset
    $.ajax({
        url:"data.php",
        dataType : "json",
        success : function(result2) {
            google.charts.load('current', {
                'packages':['corechart','bar']
            });
            google.charts.setOnLoadCallback(function() {
                console.log(result2[0]["name"])
                drawChart(result2);                 
            });
        }
    }); 

    function drawChart(result) {

        var data = new google.visualization.DataTable();
        data.addColumn('string','Name');
        data.addColumn('number','Quantity');
        var dataArray=[];
        $.each(result, function(i, obj) {
            dataArray.push([ obj.name, parseInt(obj.quantity) ]);
        });

        data.addRows(dataArray);

        var piechart_options = {
            title : 'Pie Chart: How Much Products Sold By Last Night',
            width : 400,
            height : 300
        }
        var piechart = new google.visualization.PieChart(document
                .getElementById('piechart_div'));
        piechart.draw(data, piechart_options)

        var columnchart_options = {
            title : 'Bar Chart: How Much Products Sold By Last Night',
            width : 400,
            height : 300,
            legend : 'none'
        }
        //var barchart = new google.visualization.BarChart(document
            //  .getElementById('barchart_div'));               
        //barchart.draw(data, barchart_options)

        var chart = new google.charts.Bar(document.getElementById('columnchart_material'));
        chart.draw(data, google.charts.Bar.convertOptions(columnchart_options));
    }           //have added this column chart but need to wrok out if it is best practice????

}); 

我从数据库查询中获取了一个对象,但我想知道如何从同一个数据库连接返回更多/不同的数据集?例如,如果我想使用此查询select * from product where name="Product1" OR name="Product2";

返回的数据集绘制另一个图表,该怎么办?
0: Object { id: "1", name: "Product1", quantity: "2" }
​1: Object { id: "2", name: "Product2", quantity: "3" }
​2: Object { id: "3", name: "Product3", quantity: "4" }
​3: Object { id: "4", name: "Product4", quantity: "2" }
​4: Object { id: "5", name: "Product5", quantity: "6" }
​5: Object { id: "6", name: "Product6", quantity: "11" }

值得我的PHP代码如下:

data.php

<?php
require_once 'database.php';
$stmt = $conn->prepare('select * from product');
$stmt->execute();
$results = $stmt->fetchAll(PDO::FETCH_OBJ);
echo json_encode($results); 
?>

database.php中

<?php
$conn = new PDO('mysql:host=192.168.99.100;dbname=demo','root', 'root');
?>

注意:this可能会引起您的兴趣

1 个答案:

答案 0 :(得分:1)

google图表每页加载只需要加载一次,
并非每次都需要绘制图表

另外,google.charts.load可用于代替 - &gt; $(document).ready
它会在执行回调/承诺

之前等待页面加载

建议设置类似于以下代码段...

google.charts.load('current', {
  packages: ['corechart', 'bar']
}).then(function () {
  $.ajax({
    url: 'data.php',
    dataType: 'json'
  }).done(drawChart1);

  $.ajax({
    url: 'data.php',
    dataType: 'json'
  }).done(drawChart2);
});

function drawChart1(result) {
  ...
}

function drawChart2(result) {
  ...
}