从字符串中提取子字符串

Question

I am having a particular pattern of string

page0001
page0002
.
.
.
pageMN23
pageMN24
.
page0100
page0101

and so on

I have to remove "page" and zero's after that and then pick up the page number from that. and stroe that value. Here it will return both integer and string value for example "3","4" ,"MN23", MN24". What can be used so that correct value return and it get store in correctly.

Answer 1

test = test.replace("page", "");        
int x = Integer.parseInt(test);

Just replace all the occurrences of "page" with an empty string, then Integer.parseInt() takes care of the rest.

Answer 2

Use this:

    String test = "page0100";
    boolean flag = false;
    int pageNo;
    try {
        test = test.replaceAll("page0*", ""); //Note the meta character * after 0. It removes all zeros exists after `page` string and before any non zero digit.
        pageNo = Integer.parseInt(test);
    } catch (NumberFormatException e) {
        // If NumberNumberFormatException caught here then `test` is string
        // NOT valid integer
        flag = true;
    }
    if (flag == false) {
        // Page Number is string
        // Use `test` variable here
    } else {
        // Page Number is integer
        // Use `pageNo` variable here
    }