js button click demo

<button onclick="test()"> test</button>
<script>
var logs={};
logs.log=window.console.log;
window.console.log = function() {
    alert('aa');
    logs.log.apply(window.console,['log','log','dd']);
    
};

//var stringify = JSON.stringify;

function stringify(obj) {
  var arr = [];

  for (var key in obj) {
    if (obj.hasOwnProperty(key)) {
      arr.push(encodeURIComponent(key) + "=" + encodeURIComponent(obj[key]));
    }
  }
  return arr.join('&');
}



function test()
{
  //alert("test");
  obj = {'name' : 'xiaoyu99', 'info' : {'addr' : 'wuhan', 'tel' : '136'}}
  alert(stringify(obj))
}
</script>