如何查找Java字符串中是否存在特殊字符

Question

I want to check whether a string contains # or not. Then if it contains # , I want to find the content after # .

For example,

• test#1 — This should return me 1 .
• test*1 — This should not return anything.
• test#123Test — This should return 123Test .

Please let me know. Thanx in advance.

Answer 1

I'd use simple string operations rather than a regular expression:

int index = text.indexOf('#');
return index == -1 ? "" : text.substring(index + 1);

(I'm assuming "should not return anything" means "return empty string" here - you could change it to return null if you want.)

Answer 2

// Compile a regular expression: A hash followed by any number of characters
Pattern p = Pattern.compile("#(.*)");

// Match input data
Matcher m = p.matcher("test#1");

// Check if there is a match
if (m.find()) {

  // Get the first matching group (in parentheses)
  System.out.println(m.group(1));
}