JS计算字符串长度(兼容后端PHP)

/**
* 计算字符串长度
* 参数是要计算的字符串
* 返回值当前字符串的长度
*/
function charactersLen (words) {
let tempMapWordNum = {}
let doubleByteTotal = 0 // 双字节
let chineseTotal = 0 // 汉字
let singleByteTotal = 0 // 单字节
let numTotal = 0
for (let i = 0; i < words.length; i++) {
let c = words.charAt(i)
if (c.match(/[\u4e00-\u9fa5]/)) { // 汉字
if (isNaN(tempMapWordNum[c])) {
tempMapWordNum[c] = 1
}
chineseTotal++
}
}
for (let i = 0; i < words.length; i++) {
let c = words.charAt(i)
if (c.match(/[^\x00-\xff]/)) { // 这里^表示相反的意思,Ascii码大于255的那些字符，双字节的字符
doubleByteTotal++
} else {
singleByteTotal++
}
if (c.match(/[0-9]/)) {
numTotal++
}
}
// 双字节的内容减去汉字剩下双字节标点，单字节内容减去数字剩下单字节符号
return chineseTotal + (doubleByteTotal - chineseTotal) + (singleByteTotal - numTotal) + (numTotal)
}