Java String.indexOf() 可以将正则表达式作为参数处理吗？
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Can Java String.indexOf() handle a regular expression as a parameter?
提问by Roshan
I want to capture the index of a particular regular expression in a Java String. That String may be enclosed with single quote or double quotes (sometimes no quotes). How can I capture that index using Java?
我想在 Java 字符串中捕获特定正则表达式的索引。该字符串可以用单引号或双引号括起来（有时没有引号）。如何使用 Java 捕获该索引？
eg:
例如：
capture String --> class = ('|"|)word('|"|)
采纳答案by Jigar Joshi
No.
没有。
Check source code for verification
WorkAround :Its not standard practice but you can get result using this.
解决方法：这不是标准做法，但您可以使用此方法获得结果。
Update:
更新：
CharSequence inputStr = "abcabcab283c";
String patternStr = "[1-9]{3}";
Pattern pattern = Pattern.compile(patternStr);
Matcher matcher = pattern.matcher(inputStr);
if(matcher.find()){
System.out.println(matcher.start());//this will give you index
}
OR
或者
Regex r = new Regex("YOURREGEX");
// search for a match within a string
r.search("YOUR STRING YOUR STRING");
if(r.didMatch()){
// Prints "true" -- r.didMatch() is a boolean function
// that tells us whether the last search was successful
// in finding a pattern.
// r.left() returns left String , string before the matched pattern
int index = r.left().length();
}
回答by Andreas Dolk
It's a two-step approach. First, find a match for your pattern, then (second) use Matcher#startto get the position of the matching String in the content String.
这是一个两步走的方法。首先，为您的模式找到一个匹配项，然后（第二个）用于Matcher#start获取匹配字符串在内容字符串中的位置。
Pattern p = Pattern.compile(myMagicPattern); // insert your pattern here
Matcher m = p.matcher(contentString);
if (m.find()) {
int position = m.start();
}
