按长度分割字符串.txt

function splitByLength(src, len) {
        if (src === null || src === undefined) {
            throw new Error("src 不能为 null 或 undefined");
        }

        if (src === "") {
            return [];
        }

        if (Object.prototype.toString.call(src) !== "[object String]") {
            throw new Error("src 必须是 String 类型");
        }

        len = parseInt(len);

        if (!len || len <= 0) {
            throw new Error("分割的长度不合法");
        }

        if (src.length <= len) {
            return [src];
        }

        let result = [];
        let sIndex = 0;
        let eIndex = len;
        while (src.length > sIndex) {
            result.push(src.slice(sIndex, eIndex));
            sIndex += len;
            eIndex += len;
        }

        return result;
    }