javascript - 替换 eval 以获取表单 javascript 中的值

Question

HTML 脚本

<form method="POST" name="test">
<input type="hidden" name="test2" value="test3">
<input type="submit" name="submit" value="submit" onClick="send()">
</form>

JavaScript

function send(){
   var form = document.test,
   a = eval("form.test2");
   alert(a.value); //test3
}

正如您所看到的上面的编码，我使用 eval 来获取 test2 值。但在某些 JS 检查器中，不允许 eval ..那么如何在没有 eval 函数的情况下获取 test2 值？

Answer 1

尝试这个静态示例，修改代码

var send = function() {
  var test2 = document.test.test2.value; //static access without eval
  alert(test2);
  return false;
}

<form method="post" name="test">
  <input type="text" name="test2" value="test3">
  <input type="submit" name="submit" value="submit" onclick="return send()">
  <form>

尝试这个动态示例，修改代码

var find = function(str) {
  var arr = str.split('.');
  var l = arr.length,
    i = 0;
  var el = window[arr[i++]]; //<-- we refer to js and html element right from here
  while (--l)
    el = el[arr[i++]];
  return el;
};

var send = function() {
  var prop = 'document.test.test2.value'; //<-- string name of the property to access
  var el = find(prop);
  alert(el);
  return false;
}

console.log(find('document')); //sample
console.log(find('alert')); //sample

<form method="post" name="test">
  <input type="text" name="test2" value="test3">
  <input type="submit" name="submit" value="submit" onclick="return send()">
  <form>