JS数字与字符串的相互转换

将数字转化为字符串

• value.toString()

var a = 12;
var b = a.toString();
console.log(b); // '12'

• value + ‘’

var a = 12;
var b = a + '';
console.log(b); // '12'

• String(value)

var a = 12;
var b = String(a);
console.log(b); // '12'

将字符串转换为数字

• Number(value)

var a = '12';
var b = Number(a);
console.log(b); // 12

var a = '12.50';
var b = Number(a);
console.log(b); // 12.5

• parseInt(value)

var a = '12';
var b = parseInt(a);
console.log(b); // 12

• parseFloat(value)

var a = '12.50';
var b = parseFloat(a);
console.log(b); // 12.5

• +、-运算符

var a = '12';
var b = +a;
 console.log(b); // 12

var a = '12';
var b = -a;
console.log(b); // -12