SOURCE

var data = [{
  "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"
}];
for (var i = 0; i < data.length; i++) {
  if (data[i].S_TYPE == 0) {
    alert(data[i].SELL_PRICE);
  }
}