如何在javascript中弹出数组中的元素？

Question

如何弹出从​​阵列中选择的随机数？ var number = ["a", "b", "c"];
var random = number[Math.floor(Math.random()*number.length)];

Answer 1

使用splice

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var number = ["a", "b", "c"];
var random = Math.floor(Math.random()*number.length);

console.log(number[random], ' is chosen');
var taken = number.splice(random, 1);

console.log('after removed, ', number);
console.log('number taken, ', taken);

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Answer 2

使用splice和随机数作为索引。

number.splice(random, 1);

Answer 3

您可以使用Splice从数组中删除一定数量的项目。此方法将对原始数组进行处理，并返回已删除的值。

Splice方法中的第一个参数是起点。第二个参数是要删除的项目数。

示例：

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//            0    1    2
var array = ["a", "b", "c"];
var splicedItem = array.splice(1,1);

// The array variable now equals ["a", "c"]
console.log("New Array Value: " + array);
// And the method returned the removed item "b"
console.log("Spliced Item: " + splicedItem);

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您还可以在第一个参数中使用负数开始从数组末尾向后计数。

示例：

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//            -6   -5   -4   -3   -2   -1
var array2 = ["a", "b", "c", "d", "e", "f"];
var splicedItem2 = array2.splice(-3, 2);

// The array2 variable now equals ["a", "b", "c", "f"]
console.log("New Array Value: " + array2);
// The values removed were "d" and "e"
console.log("Spliced Item: " + splicedItem2);

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您甚至可以通过包含其他参数将新项目插入到数组中。如果您不想，也不需要将拼接的项目返回到新的变量。

示例：

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var array3 = ["a", "b", "c", "d", "e", "f"];

array3.splice(2, 2, "Pink", "Mangoes");

// The array3 value is now ["a", "b", "Pink", "Mangoes", "e", "f"]
console.log("New Array Value: " + array3);

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