字符串处理 - java 如何得到"{{ xxx }}"中xxx内容？

Question

如何得到两个双括号里面内容，由于一个字符串中可能有多组双括号，所以不好用substring.indexOf("{{")...求助

String str="my name is {{ name }},my email is {{ email }}，my school is {{ xxx }}";
//如何得到多组花括号中内容（name，email，xxx）？分割之类的都不好分？

Answer 1

用正则表达式吧，如下：

public static void main(String[] args) {
        String str="my name is {{ name }},my email is {{ email }}，my school is {{ xxx }}"; 
        Pattern pattern = Pattern.compile("\\{\\{([^\\}]+)\\}\\}"); 
        Matcher matcher = pattern.matcher(str); 
        while(matcher.find()){ 
            String t = matcher.group(1); 
            System.out.println(t); 
        }

    }

Answer 2

1.手动分割
2.正则表达式

推荐正则

Answer 3

https://msdn.microsoft.com/zh-cn/library/aa989779(v=vs.80).aspx
善用indexOf的第二个参数，没事多看msdn。

String str="my name is {{ name }},my email is {{ email }}，my school is {{ xxx }}";
int index=0;
for(int i=0;i<str.length();i++
{
    int index1 = str.indexOf("{{ ",index);
    if (index1==-1) break;
    int index2 = str.indexOf(" }}",index1+3);
    if (index2==-1) break;
    index=index2+3;
    string fragment=str.substring(index1+3,index2);
    // fragment分别是"name", "email", "xxx"
}

Answer 4

public static void main(String[] args) {

    ArrayList<String> keys = new ArrayList<String>();
    String str = "my name is {{ name }},my email is {{ email }}，my school is {{ xxx }}";
    Pattern p = Pattern.compile("\\{\\{\\s*(\\w*)\\s*\\}\\}");
    Matcher m = p.matcher(str);

    while (m.find()) {
        keys.add(m.group(1));
    }
    System.out.println(keys);
}