javascript - 在 Javascript 中检测数字溢出

Question

javascript 中是否有任何内置函数会通知数字数据类型的算术运算溢出？就像 C# 和 Java 一样。

Answer 1

从这个网站检查:isSafeInteger

var x = Number.MAX_SAFE_INTEGER + 1;
var y = Number.MAX_SAFE_INTEGER + 2;

    console.log(Number.MAX_SAFE_INTEGER);
    // expected output: 9007199254740991

    console.log(x);
    // expected output: 9007199254740992
    console.log(y);
    // expected output: 9007199254740992
    console.log(x === y);
    // expected output: true
    
function warn(a) {
  if (Number.isSafeInteger(a)) {
    return 'Precision safe.';
  }
  return 'Precision may be lost!';
}

    console.log(warn(Number.MAX_SAFE_INTEGER));
    // expected output: "Precision safe."

    console.log(warn(x));
    // expected output: "Precision may be lost!"
    console.log(warn(y)); 
    // expected output: "Precision may be lost!"