string str = "1,2,3,4,5,6,7";
string[] strArray = str.Split(','); //字符串转数组
str = string.Empty;
str = string.Join(",", strArray);//数组转成字符串
string str = "1,2,3,4,5,6,7";
string[] strArray = str.Split(','); //字符串转数组
str = string.Empty;
str = string.Join(",", strArray);//数组转成字符串