Array concat

Array concat 的簡單範例

by Joseph Chiang

JavaScript

// concat 是 Concatenate（串連）的縮寫
// 可將多個陣列合併
var group1 = ["tellis", "amaris"],
    group2 = ["ashley", "gary", "alen"],
    group3 = ["robert", "knock"],
    all;
all = group1.concat(group2, group3);
document.write("all = " + all.join(","));
    
document.write("<br><br>");
    
// 我只有用過陣列的複製
var items = ["html", "javascript", "css"],
    newItems;

newItems = [].concat(items);

// 雖然較不容易理解，但是效率比 for 好多了
/*
for (var i = 0, j = items.length; i < j; i++) {
    newItems.push(items[i]);
}
*/
document.write("newItems = " + newItems.join(","));

// String 的 concat，就好懂多了吧 :D
var str1 = "html",
    str2 = ",css",
    str3 = ",javascript";

str1.concat(str2, str3);