lovecoding
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VIP30


			
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  <script>
    //toString() 把数组转换为数组值（逗号分隔）的字符串
    // var fruits = ["Banana", "Orange", "Apple", "Mango"];
    // var a = fruits.toString()
    // console.log(a)

    //join() 方法也可将所有数组元素结合为一个字符串。
    // var fruits = ["Banana", "Orange","Apple", "Mango"];
    // var a = fruits.join('*')
    // console.log(a)

    //pop() 方法从数组中删除最后一个元素
    // var fruits = ["Banana", "Orange","Apple", "Mango"];
    // var a = fruits.pop()
    // console.log(a)
    // console.log(fruits)

    //push() 方法（在数组结尾处）向数组添加一个新的元素
    // var fruits = ["Banana", "Orange","Apple", "Mango"];
    // // fruits.push('kiwi')
    // console.log(fruits.push('kiwi'))

    //shift() 方法会删除首个数组元素，并把所有其他元素“位移”到更低的索引
    // var fruits = ["Banana", "Orange","Apple", "Mango"];
    // // fruits.shift()
    // console.log(fruits.shift())

    //unshift() 方法（在开头）向数组添加新元素，并“反向位移”旧元素
    // var fruits = ["Banana", "Orange","Apple", "Mango"];
    // console.log(fruits.unshift('kiwi'))

    //使用 JavaScript delete 运算符来删除
    //使用 delete 会在数组留下未定义的空洞。请使用 pop() 或 shift() 取而代之
    // var fruits = ["Banana", "Orange","Apple", "Mango"];
    // delete fruits[0]
    // console.log(fruits)

    //splice() 方法可用于向数组添加新项
    //splice(第一个参数代表添加元素的位置，第二个代表删除元素的个数)
    // var fruits = ["Banana", "Orange"  ,"Apple", "Mango"];
    // // fruits.splice(2,0,'kiwi','pear')
    // // console.log(fruits)

    // fruits.splice(0,2)
    // console.log(fruits)

    //concat() 方法通过合并（连接）现有数组来创建一个新数组
    // var myGirls = ["Cecilie", "Lone"];
    // var myBoys = ["Emil", "Tobias", "Linus"];
    // var myChildren = myGirls.concat(myBoys)
    // console.log(myChildren)


    //slice() 方法用数组的某个片段切出新数组。
    var fruits = ["Banana", "Orange", "Lemon", "Apple", "Mango"];
    var num = fruits.slice(1,3) //[1,3)
    console.log(fruits)
    console.log(num)
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