United States Department of Agriculture 美国农业部网站数据自动下载小脚本

帮对象写的自动点击页面的小脚本，如果有需要的可以试试，(#^.^#)
https://apps.fas.usda.gov/gats/ExpressQuery1.aspx
 1 var year = '1991';
 2 
 3 var box3 = document.querySelector("#ctl00_ContentPlaceHolder1_lb_Partners");
 4 box3.value='ALLRG';
 5 box3 = document.querySelector("#ctl00_ContentPlaceHolder1_lb_Products");
 6 box3.value='M1';
 7 box3 = document.querySelector("#ctl00_ContentPlaceHolder1_ddlValueUnit");
 8 box3.value='M';
 9 box3 = document.querySelector("#ctl00_ContentPlaceHolder1_ddlDateSeries");
10 box3.value='Annual';
11 box3 = document.querySelector("#ctl00_ContentPlaceHolder1_ddlOrderBy");
12 box3.value='CODE';
13 box3 = document.querySelector("#ctl00_ContentPlaceHolder1_ddlInDetail");
14 box3.value='Product';
15 box3 = document.querySelector("#ctl00_ContentPlaceHolder1_ddlCalculation");
16 box3.value='';
17 
18 box3 = document.querySelector("#ctl00_ContentPlaceHolder1_ddlStartYear");
19 box3.value= year;
20 box3.dispatchEvent(new Event('change'));
21 box3 = document.querySelector("#ctl00_ContentPlaceHolder1_ddlEndYear");
22 box3.value= year;
23 box3.dispatchEvent(new Event('change'));
24 
25 
26 function clickStep()
27  {
28      if (document.querySelector("#overlay").style.display == 'block') {
29          setTimeout("clickStep()", 1000);
30          return;
31      } 
32      console.log("触发点击事件")
33      document.querySelector("#ctl00_ContentPlaceHolder1_btnRetrieveData").click();
34  }
35  setTimeout("clickStep()", 1000);
36 
37 String.prototype.startWith=function(str){
38 var reg=new RegExp("^"+str);
39 return reg.test(this);
40 }
41 var clicked = false;
42 function doExpand() {
43     box3 = document.querySelector("#ctl00_ContentPlaceHolder1_UltraWebTab1__ctl1_grdExpressQuery_GridView1");
44     var rows = box3.rows;
45     var inputs = [];
46     for (var index in rows) {
47         var length = rows[index].cells ? rows[index].cells.length : 0;
48         if (length < 4) {
49             continue;
50         } 
51         var nodes = rows[index].cells[3].childNodes;
52         if (nodes.length == 0) {
53             continue;
54         }
55         if (nodes[0].nodeName == '#text') {
56             continue;
57         }
58         var cell5Text = rows[index].cells[4].innerText;
59         if (!cell5Text.startWith('Bulk Total') && !cell5Text.startWith('Intermediate Total') && !cell5Text.startWith('Consumer Oriented Total')) {
60             continue;
61         }
62 
63         var input = nodes[0];
64 
65         if(input.value == '-') {
66             continue;
67         }
68 
69         clicked = true;
70         input.click();
71         break;
72     }
73 }
74 
75 var index = 0;
76 function expandStep()
77  {
78      if (document.querySelector("#overlay").style.display == 'block' || document.querySelector("#ctl00_ContentPlaceHolder1_UltraWebTab1") == null) {
79          setTimeout("expandStep()", 1000);
80          return;
81      } 
82      console.log((index++) + "打开,total:" );
83      doExpand();
84      if (!clicked) {
85          alert("展开完成，请下载")
86          return;
87      } else {
88          clicked = false;
89      }
90      expandStep();
91  }
92 
93  setTimeout("expandStep()", 5000);