Question

这就是我想要的：

>> var uint n = 0;
<- undefined (output by firefox dev console, I don't know what this means)
>> n;
<- 0;
>> n - 1;
<- 4294967295 (2^32-1)

那么如何在javascript中声明一个变量，以便它是无符号的？提前谢谢。

Answer 1

LK＆＃34;我

这是你的意思吗？

var unsigned = someVar >>>0

JavaScript C Style Type Cast From Signed To Unsigned

Answer 2

如果您确实需要未签名，请检查Uint32Array on MDN。

但是，既然你没有从你的无符号值中获得任何东西，那么简单的模数运算可能会更好吗？

＆＃13;

//Create var as array of length 1
var arr = new Uint32Array(1);
//set first value to 1
arr[0] = 1;
//output contents
console.log(arr);
//substract to "negative"
arr[0] -= 2;
//output contents
console.log(arr);

＆＃13;

<强>模量

＆＃13;

//Object with setter, to make it simpler
var my_obj = Object.create({
  //This is our value
  value: 0
}, {
  //This is our setter
  set: {
    value: function(a) {
      //Make incoming value a modulus of some integer
      //I just use 1000 for the example
      var max = 1000;
      a = a % max;
      //Force a positive
      while (a < 0) {
        a += max;
      }
      //Set value
      this.value = a;
      //Return object regerence for chaining
      return this;
    }
  }
});
console.log("0:", my_obj.value);
my_obj.set(500);
console.log("500:", my_obj.value);
my_obj.set(-0);
console.log("-0:", my_obj.value);
my_obj.set(-1);
console.log("-1:", my_obj.value);
my_obj.set(-100);
console.log("-100:", my_obj.value);
my_obj.set(-0);
console.log("-0:", my_obj.value);

＆＃13;

或使用功能：

＆＃13;

function modulusMax(value, a) {
  //Make incoming value a modulus of some integer
  //I just use 1000 for the example
  var max = 1000;
  a = a % max;
  //Force a positive
  while (a < 0) {
    a += max;
  }
  //Set value
  value = a;
  //Return object regerence for chaining
  return value;
}

var v = 0;

console.log("0:", modulusMax(v, 0));
console.log("500:", modulusMax(v, 500));
console.log("-0:", modulusMax(v, -0));
console.log("-1:", modulusMax(v, -1));
console.log("-100:", modulusMax(v, -100));
console.log("1100:", modulusMax(v, 1100));
console.log("-0:", modulusMax(v, -0));

＆＃13;

Answer 3

每个加2的数字都是正数，所以...

let uint = number =>  Math.sqrt(Math.pow(number, 2));
console.log(uint(-4)); // 4

如何在javascript中声明unsigned int变量？

3 个答案: