JavaScript數組的 unshift()方法將一種或多種元素添加到數組的開頭,并返回該數組的新長度。
語法
array.unshift( element1, ..., elementN );
下面是參數的詳細信息:
返回值:
返回新數組的長度。這將返回undefined(未定義)在IE瀏覽器。  
例子:
<html><head><title>JavaScript Array unshift Method</title></head><body><script type="text/javascript">var arr = new Array("orange", "mango", "banana", "sugar");var length = arr.unshift("water");document.write("Returned array is : " + arr );document.write("<br /> Length of the array is : " + length );</script></body></html>這將產生以下結果:
Returned array is : water,orange,mango,banana,sugarLength of the array is : 5
新聞熱點
疑難解答