如何通过搜索某些字符从另一个字符串生成subString

Question

String x = "ID:12 Patient Name:...";    
String z = = x.substring(3, x.indexOf(' P'));

I want to get the ID number

Answer 1

You're almost there. Just use something like this:-

String z = x.substring(x.indexOf("ID:")+3, x.indexOf("Patient")-1);

+3 - Because you don't need the ID:

-1 - Because you don't need the space before the Patient

This is taking into account that there is a SINGLE space before Patient , if not, as @BuhakeSindi suggested use the trim() method like this:-

String z = x.substring(x.indexOf("ID:")+3, x.indexOf("Patient"));
z = z.trim();