I have example text:

var text = `class Eee {
   test(){
     console.log("123");
   }
}
use(123, Eee);

class Ttt {
   test(){
     console.log("123");
   }
}
use(456, Ttt);


class Ooo {
   test(){
     console.log("123");
   }
}
use(111, Ooo);
`;

And I wont get part text for example:

`class Ttt {
   test(){
     console.log("123");
   }
}
use(456, Ttt);`

If I use RegEx:

let result = text.match(/^class Ttt \{(.*)/gm); 

I have result: [ 'class ttt {' ]

If I use RegEx:

let result = text.match(/^class Ttt \{(.*)\}/gm); 

or

let result = text.match(/^class Ttt \{(.*)use\([\b].Ttt\);/gm);

I have result: null. How can I get the entire piece of text I want, not the first line?

CodePudding user response：

You specified where the match should start, but you also have to specify where is should end.

If the end for example is at the start of a new line and the next line should be use(456, Ttt); on it's own:

^[^\S\n]*class Ttt {[^]*?\n\s*}\s*\n\s*use\(.*\);$

Note that \s can also match newlines.

The pattern in parts:

• ^ Start of string
• [^\S\n]* Match optional whitespace chars without newlines
• class Ttt { Match literally
• [^]*? Match any character including newlines, as few as possible
• \n\s*}\s* Match a newline and } between optional whitespace chars
• \nuse\(.*\); Match a newline and use(...);
• $ End of string

Regex demo

var text = `class Eee {
   test(){
     console.log("123");
   }
}
use(123, Eee);

class Ttt {
   test(){
     console.log("123");
   }
}
use(456, Ttt);


class Ooo {
   test(){
     console.log("123");
   }
}
use(111, Ooo);
`;

const regex = /^[^\S\n]*class Ttt {[^]*?\n\s*}\s*\n\s*use\(.*\);$/m;
const m = text.match(regex);

if (m) {
  console.log(m[0]);
}

CodePudding user response：

For what it's worth, here's a non-regex version:

'class '   text.split('class ')[1]

var text = `class Eee {
   test(){
     console.log("123");
   }
}
use(123, Eee);

class Ttt {
   test(){
     console.log("123");
   }
}
use(456, Ttt);


class Ooo {
   test(){
     console.log("123");
   }
}
use(111, Ooo);
`;

console.log('class '   text.split('class ')[1])