求正则达人解答

Question

需求是这样的，input输入框只能输入数字和小数，开头不能是点和零，小数最多只能输入两位，谢谢！！

Answer 1

<input id="input">

var reg = /^[1-9]\d*(\.\d{0,2})?$|^0(\.\d{0,2})?$|^-([1-9]{1}\d*(\.\d{0,2})?)?$|^-(0(\.\d{0,2})?)?$/;

var input = document.getElementById('input');

var oldValue = '';
input.addEventListener('input',function(){
  console.log(input.value)
    if(input.value && !reg.test(input.value)){
      input.value = oldValue;
    }  
  oldValue = input.value;
});

input.addEventListener('change',function(){
   if(input.value.endsWith('.') || input.value.endsWith('-')){
     input.value = input.value.slice(0,-1);
   }
});

https://codepen.io/randyou/pe...

Answer 2

/^d*(?:.d{0,2})?$/
参考文章: http://www.jb51.net/article/8...