发布于 2017-01-05 03:35:15 | 228 次阅读 | 评论: 0 | 来源: 网友投递

这里有新鲜出炉的Javascript教程，程序狗速度看过来！

JavaScript客户端脚本语言

Javascript 是一种由Netscape的LiveScript发展而来的原型化继承的基于对象的动态类型的区分大小写的客户端脚本语言，主要目的是为了解决服务器端语言，比如Perl，遗留的速度问题，为客户提供更流畅的浏览效果。

---

为了实现这样的数据显示出来三个序列，分别为郑州、新乡、安阳的电量，就需要自己实现对这样数据的转换，转换成如下的形式：

月份 郑州-电量 新乡-电量 安阳-电量
201201 33 29 23
201202 35 26 25
201203 34 27 24
201204 36 28 26
201205 34.3 28.8 24.3
这样，Ext的图表就能把它显示成三个序列了。
我写了如下的函数实现这个功能：

function CovertData(jsonData,idField, fromField, toField){ 
var result = [], curRecord =null, num; 
var fromFields = fromField.split(','); 
// 循环整个数组：[{...},{...},{...},...] 
for(var idx=0;idx<jsonData.length;idx++){ 
num = findIdx(result, idField, jsonData[idx][idField]); 
if(num!=-1){ 
curRecord = result[num]; 
} 
else{ 
curRecord = {}; 
}; 
// 循环每个json对象中的字段 
for(var key in jsonData[idx]){ 
// 处理转换的数据内容 
for(var i=0;i<fromFields.length;i++){ 
if(key == fromFields[i]){ 
curRecord[jsonData[idx][toField]+'-' + fromFields[i]] = jsonData[idx][key]; 
break; 
} 
} 
// 除数据内容外，只处理标识字段数据 
if(key == idField){ 
curRecord[key] = jsonData[idx][key]; 
} 
} 
if(num==-1){ 
result.push(curRecord); 
} 
} 
return result; 
} 

function findIdx(jsonData, columnName, value){
for(var idx = 0;idx<jsonData.length;idx++){
if(jsonData[idx][columnName]==value)
return idx;
}
return -1;
}
JsTestDriver的测试代码如下：
TestCase("Test json data row to column",{
setUp:function(){
this.jsonData = [{yearmonth:201201,ppq:23,spq:27,company:'dfsoft'},
{yearmonth:201202,ppq:33,spq:38,company:'dfsoft'},
{yearmonth:201203,ppq:43,spq:49,company:'dfsoft'},
{yearmonth:201204,ppq:53,spq:51,company:'dfsoft'},
{yearmonth:201201,ppq:29,spq:26,company:'vcom'},
{yearmonth:201202,ppq:34,spq:38,company:'vcom'},
{yearmonth:201203,ppq:48,spq:43,company:'vcom'},
{yearmonth:201204,ppq:52,spq:59,company:'vcom'}];

var fromField = 'ppq,spq', toField = 'company', idField = 'yearmonth';
this.resultData = CovertData(this.jsonData,idField,fromField, toField);
},
"test store has columns":function(){
var month1 = this.resultData[findIdx(this.resultData,'yearmonth',201201)];
var month2 = this.resultData[findIdx(this.resultData,'yearmonth',201202)];
var month3 = this.resultData[findIdx(this.resultData,'yearmonth',201203)];
var month4 = this.resultData[findIdx(this.resultData,'yearmonth',201204)];

assertEquals(4,this.resultData.length);
assertEquals('23',month1['dfsoft-ppq']);
assertEquals('29',month1['vcom-ppq']);
assertEquals('33',month2['dfsoft-ppq']);
assertEquals('34',month2['vcom-ppq']);
assertEquals('43',month3['dfsoft-ppq']);
assertEquals('48',month3['vcom-ppq']);
assertEquals('53',month4['dfsoft-ppq']);
assertEquals('52',month4['vcom-ppq']);

assertEquals('27',month1['dfsoft-spq']);
assertEquals('26',month1['vcom-spq']);
assertEquals('38',month2['dfsoft-spq']);
assertEquals('38',month2['vcom-spq']);
assertEquals('49',month3['dfsoft-spq']);
assertEquals('43',month3['vcom-spq']);
assertEquals('51',month4['dfsoft-spq']);
assertEquals('59',month4['vcom-spq']);
}
})