javascript - 警告变量值(alert a variable value)

Question

How do I display the value of a variable in javascript in an alert box?

(如何在警告框中的javascript中显示变量的值？)

For example I've got a variable x=100 and alert(x) isn't working.

(例如，我有一个变量x = 100而alert（x）不起作用。)

the script used in grease monkey is here

(油脂猴子使用的脚本就在这里)

var inputs = document.getElementsByTagName('input');

var new;
for (i=0; i<inputs.length; i++) {
  if (inputs[i].getAttribute("name") == "ans") {   
new=inputs[i].getAttribute("value"));

alert(new)

  }
}

  ask by technocrat translate from so

Answer 1

A couple of things:

(有几件事：)

1. You can't use new as a variable name, it's a reserved word.

   (你不能使用new作为变量名，它是一个保留字。)

2. On input elements, you can just use the value property directly, you don't have to go through getAttribute .

   (在input元素上，您可以直接使用value属性，而不必通过getAttribute 。)

   The attribute is "reflected" as a property.

   (该属性被“反映”为属性。)

3. Same for name .

   (name相同。)

So:

(所以：)

var inputs, input, newValue, i;

inputs = document.getElementsByTagName('input');
for (i=0; i<inputs.length; i++) {
    input = inputs[i];
    if (input.name == "ans") {   
        newValue = input.value;
        alert(newValue);
    }
}