如何去掉陣列重複的數字？
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
</head>
<body>
<script>
var arr=[1,2,3,3,4,4,5,5,6,1,9,3,25,4];
Array.prototype.repetition = function(){//在原型自定義repetition方法
var newArray = [];//假設臨時儲存的陣列；
for(var i = 0; i < this.length; i++)//遍歷當前陣列
{
if(newArray.indexOf(this[i]) == -1)//如果當前陣列第i個已經未存進臨時陣列，則新增
{
newArray.push(this[i]);
}
}
return newArray;//返回陣列內容
}
var array = arr.repetition();//呼叫在原型自定義的repetition方法
console.log(array);
</script>
</body>
</html>
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<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
</head>
<body>
<script>
var arr = ["選項", "選項2", "選項2", "選項3", "選項2", "選項1", "選項1", "選項1"];
var newArr = [];
for(var i = 0; i < arr.length; i++)
{
if(arr.indexOf(arr[i]) == i)
{
newArr.push(arr[i]);
}
}
console.log(newArr);
</script>
</body>
</html>