使用js截取前len字节的字符串,
str 要截取的字符穿
len要截取的长度,根据字节计算
suffix截取前len个后,其余的字符的替换字符一般用“…”
function cutString(str,len,suffix){if(!str) return "";if(len<= 0) return "";if(!suffix) suffix = "";var templen=0;for(var i=0;i<str.length;i++){if(str.charCodeAt(i)>255){templen+=2;}else{templen++}if(templen == len){return str.substring(0,i+1)+suffix;}else if(templen >len){return str.substring(0,i)+suffix;}} return str;}