JavaScript中的charCodeAt方法的用法:该方法用于返回指定位置的字符的Unicode编码。语法是【string.charCodeAt(index)】,参数index表示字符串中某个位置的数字,即字符在字符串中的下标。
JavaScript charCodeAt方法怎么用?
JavaScript charCodeAt() 方法
定义和用法
charCodeAt() 方法可返回指定位置的字符的 Unicode 编码。
字符串中第一个字符的位置为 0, 第二个字符位置为 1,以此类推。
语法
string.charCodeAt(index)
参数值
参数
index 必需。表示字符串中某个位置的数字,即字符在字符串中的下标。
返回值
Number 返回在指定的位置的字符的 Unicode 编码。
实例
返回字符串中最后一个字符的 Unicode 编码:
var str = "HELLO WORLD"; var n = str.charCodeAt(str.length-1);
n 输出结果:
68
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