字符串转int类型 怎么转不了

String tmp = ReadContentTXT(context, "txt.txt");
int ci = 0;
char tp;
char num[] = new char[10];
String to;
for (int j = 0; j < tmp.length(); j++) {
tp = tmp.charAt(j);

if(tp != '\r' && tp != '\n')
{
switch(tp)
{
case ',':
ci = 0;
to = String.valueOf(num);
to.trim();
Integer.parseInt(to);
System.out.println(to);
Arrays.fill(num, ' ');
break;
case '|':
System.out.print("faf");
break;
case ';':
break;
default:
num[ci] = tp;
ci++;
break;
}
}

}