JavaScript中number和~~比较、API

function replaceNumber() { console.log(Number(null)); // 0 console.log(~~null); // 0 console.log("--------------------------------------------------------------"); console.log(Number(undefined)); // NaN console.log(~~undefined); // 0 console.log("--------------------------------------------------------------"); console.log(Number(123)); // 123 console.log(~~123); // 123 console.log("--------------------------------------------------------------"); console.log(Number("123")); // 123 console.log(~~"123"); // 123 console.log("--------------------------------------------------------------"); console.log(Number("abc")); // NaN console.log(~~"abc"); // 0 console.log("--------------------------------------------------------------"); console.log(Number(NaN)); // NaN console.log(~~NaN); // 0 } replaceNumber();