正则 数字保留两位小数
^[0-9]+(.[0-9]{1,2})?$ 数字保留两位小数
const handleChange = val => {
let num = val.toString()
if (num.indexOf('.') === 0) {
num = `0${num}`
}
num = num.replace(/[^\d.]/g, '')
num = num.replace(/\.{2,}/g, '.')
num = num.replace('.', '$#$').replace(/\./g, '').replace('$#$', '.')
num = num.replace(/^(-)*(\d+)\.(\d\d).*$/, '$1$2.$3')
if (num.indexOf('.') < 0 && num !== '') {
num = parseFloat(num)
}
return num
}