function substringimport { substring } from "https://deno.land/x/pagic@v1.6.1/src/utils/substring.ts"; substring(str: string,n: number,suffix?,)截取指定长度的中英文混合字符串 Parametersstr: string待截取的字符串 n: number截取长度(中文字符为英文的 double) optionalsuffix = [UNSUPPORTED]