public static void main(String args[]) {
String str = "1256789";
String qq[] = str.split("");
ArrayList list = new ArrayList();
for (int i = 0; i < qq.length; i++)
list.add(qq[i]);
list.remove(0);
list.add(2, new String("3"));
list.add(3, new String("4"));
Iterator it = list.iterator();
for (Iterator iter = list.iterator(); iter.hasNext();) {
String str1 = (String) iter.next();
System.out.println(str1);
}
}
String str = "1256789";
String qq[] = str.split("");
ArrayList list = new ArrayList();
for (int i = 0; i < qq.length; i++)
list.add(qq[i]);
list.remove(0);
list.add(2, new String("3"));
list.add(3, new String("4"));
Iterator it = list.iterator();
for (Iterator iter = list.iterator(); iter.hasNext();) {
String str1 = (String) iter.next();
System.out.println(str1);
}
}
{
StringBuffer s = new StringBuffer("1256789");
System.out.println(s);
s.insert(2,"34");
System.out.println(s);
}
后面就用个for循环把缺掉的数字全补上
String oldStr="125789";
int min=10, max=0;
for (int i = 0; i<oldStr.length()-1; i++){
int nn=Integer.parseInt(oldStr.substring(i,i+1));
if (min > nn) min=nn;
if (max < nn) max=nn;
}
String result="";
for( int i=min; i<=max; i++)
result=result+String.valueOf(i);
=========
String qq[] = str.split("");进行这句后,第一个元素为“”