SOURCE

var data=[
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    "S_TYPE": 0,
    "SELL_PRICE": 23,
    "SERVICE_NO": "1001",
    "NUM": 0,
    "COST_PRICE": 500,
    "NAME": "实名身份认证-简版"
  },
  {
    "S_TYPE": 1,
    "SELL_PRICE": 12,
    "SERVICE_NO": "2003",
    "NUM": 0,
    "COST_PRICE": 0
  },
   {
    "S_TYPE": 0,
    "SELL_PRICE": 21,
    "SERVICE_NO": "1002",
    "NUM": 0,
    "COST_PRICE": 500,
    "NAME": "实名身份认证"
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]; 
     for (var i = 0; i < data.length; i++) {
          if(data[i].S_TYPE == 0){
            alert(data[i].SELL_PRICE);
          }
      }