pop()
定义和用法
pop() 方法用于删除并返回数组的最后一个元素。
语法
arrayObject.pop()
返回值
arrayObject 的最后一个元素。
说明
pop() 方法将删除 arrayObject 的最后一个元素,把数组长度减 1,并且返回它删除的元素的值。
如果数组已经为空,则 pop() 不改变数组,并返回 undefined 值。
实例
在本例中,我们将创建一个数组,然后删除数组的最后一个元素。请注意,这也会改变数组的程度:
var arr = new Array(3)arr[0] = "George"arr[1] = "John"arr[2] = "Thomas"document.write(arr)document.write("
")document.write(arr.pop())document.write("
")document.write(arr)var arr = new Array(3)arr[0] = "George"arr[1] = "John"arr[2] = "Thomas"document.write(arr)document.write("
")document.write(arr.pop())document.write("
")document.write(arr)var arr = new Array(3)arr[0] = "George"arr[1] = "John"arr[2] = "Thomas"document.write(arr)document.write("
")document.write(arr.pop())document.write("
")document.write(arr)var arr = new Array(3)arr[0] = "George"arr[1] = "John"arr[2] = "Thomas"document.write(arr)document.write("
")document.write(arr.pop())document.write("
")document.write(arr)var arr = new Array(3)arr[0] = "George"arr[1] = "John"arr[2] = "Thomas"document.write(arr)document.write("
")document.write(arr.pop())document.write("
")document.write(arr)var arr = new Array(3)arr[0] = "George"arr[1] = "John"arr[2] = "Thomas"document.write(arr)document.write("
")document.write(arr.pop())document.write("
")document.write(arr)<script type="text/javascript">
var arr = new Array(3)
arr[0] = "George"
arr[1] = "John"
arr[2] = "Thomas"
document.write(arr)
document.write("<br />")
document.write(arr.pop())
document.write("<br />")
document.write(arr)
</script>
var arr = new Array(3)arr[0] = "George"arr[1] = "John"arr[2] = "Thomas"document.write(arr)document.write("
")document.write(arr.pop())document.write("
")document.write(arr)
输出:
George,John,Thomas
Thomas
George,John