...
var mesAsBoolean=Boolean(mes);
console.log(messageAsBoolean); //true 非空字符串 非零数字 任何对象
console.log(mesAsBoolean); //false 空字符串 0和NaN null undefined
console.log(Number.MIN_VALUE); //最小值 5e-324
console.log(Number.MAX_VALUE); //最大值 1.7976931348623157...
