從javascript中刪除最後n個字母

Question

如何檢查一個數組是否包含JavaScript中的arr？通常情況下，我會期待一個subString方法，但似乎沒有一個。什麼是合理的方法來檢查這個？

arr=["aaaaaa-2","bbbbbbbb-2","zzzz-3","ffddssaa-1","sssssss-3","areyo-1"] 

我想最後兩個字符從列表中刪除，我試着用下面的代碼，但沒有使用這些，任何一個可以建議我

arr.substring(0, -2) 

我需要陣列狀

["aaaaaa","bbbbbbbb","zzzz","ffddssaa","sssssss","areyo"] 

Answer 1

var arr=["aaaaaa-2","bbbbbbbb-2","zzzz-3","ffddssaa-1","sssssss-3","areyo-1"]; 

for(var i in arr){ 
    consile.log(arr[i].substr(0,arr[i].lastIndexOf("-")); //here is your value 
} 

Answer 2

遍歷元素並應用substring()的方法，對於使用map()

var arr = ["aaaaaa-2", "bbbbbbbb-2",, "zzzz-3", "ffddssaa-1", "sssssss-3", "areyo-1"]; 
 

 
var res = arr.map(function(v) { 
 
    return v.substring(0, v.length-2); 
 
}); 
 

 
console.log(res);

Answer 3

與剛剛嘗試：陣列的

arr.map(function(v){ 
    return v.substr(0, v.length - 2); 
}); 

Answer 4

使用地圖的方法。

arr = arr.map(function(item){return item.slice(0, item.length-2)}); 

Answer 5

for(var i=0;i<arr.length;i++) { 
    arr[i] = arr[i].substring(0, arr[i].length-2); 
} 

Answer 6

最簡單的事情是使用map功能

var arr=["aaaaaa-2","bbbbbbbb-2","zzzz-3","ffddssaa-1","sssssss-3","areyo-1"]; 
console.log(arr.map(function (e){ 
    return e.slice(0, -2); 
})); 

Answer 7

首先爲您的信息substring方法工作在string不是array這裏ARR是array的代碼應該是這樣的： -

for(var i = 0;i<arr.length;i++) 
    { 
    arr[i].substring(0, arr[i].length-2); 
    }