我不明白為什么這不起作用（在陣列/if陳述句中指定一個范圍）-有解無憂

var guestList = ['Gabe', 'name2', 'name3', 'name4', 'name5']

var guestName = prompt('Hello, what is your name')

var range = guestList.slice(0, guestList.length)

if (guestList.includes(range)) {
    alert(`Hello ${guestName} and welcome to EVENT NAME`)


} else {
    alert(`Hello ${guestName}, you are not on the guest list`)
}

uj5u.com熱心網友回復：

這是你想要的嗎？

var guestList = ['Gabe', 'name2', 'name3', 'name4', 'name5']

var guestName = prompt('Hello, what is your name')

if (guestList.includes(guestName)) {
    alert(`Hello ${guestName} and welcome to EVENT NAME`)
} else {
    alert(`Hello ${guestName}, you are not on the guest list`)
}

uj5u.com熱心網友回復：

我想這很好用：

var guestList = ['Gabe', 'name2', 'name3', 'name4', 'name5']

var guestName = prompt('Hello, what is your name')

if (guestList.includes(guestName)) { alert("Hello"  guestName  "and welcome to EVENT NAME")

} else { alert("Hello "  guestName ", you are not on the guest list") }

uj5u.com熱心網友回復：

洗掉range因為它沒用，并range在這一行替換為guestName

if (guestList.includes(guestName)) {....

Prompt()回傳一個用戶輸入的值。

var guestList = ['Gabe', 'name2', 'name3', 'name4', 'name5']

var guestName = prompt('Hello, what is your name')

/* Add this line if you want the comparison
to be case insensitive 
*/
// guestList = guestList.map(name => name.toLowerCase());

/* And replace guestName with
guestName.toLowerCase() in the "if"
statement as well.
*/
if (guestList.includes(guestName)) {
  alert(`Hello ${guestName} and welcome to EVENT NAME`)
} else {
  alert(`Hello ${guestName}, you are not on the guest list`);
}

uj5u.com熱心網友回復：

看看你的那一行代碼var range = guestList.slice(0, guestList.length)。現在range是一個子陣列，guestList您正在嘗試驗證guestList它是否包含不正確的元素。 range

我認為您正在嘗試這樣做：

var guestList = ['Gabe', 'name2', 'name3', 'name4', 'name5']

var guestName = prompt('Hello, what is your name')

if (guestList.includes(guestName)) {
    alert(`Hello ${guestName} and welcome to EVENT NAME`)


} else {
    alert(`Hello ${guestName}, you are not on the guest list`)
}

轉載請註明出處，本文鏈接：https://www.uj5u.com/qita/434358.html

標籤：javascript 数组

上一篇：使用HTML集合進行復雜的動態部分分離

下一篇：C中結構中的元素數