I'm trying to find and replace a word in a string
Example:
let string =
`
Title: Hello World
Authors: Michael Dan
`
I need to find the Hellow World and replace with whatever I want, here is my attempt:
const replace = string.match(new RegExp("Title:" + "(.*)" + "Authors:")).replace("Test")
When you replace some text, it is not necessary to run String#match or RegExp#exec explicitly, String#replace does it under the hood.
You can use
let string = "\nTitle: Hello World\nAuthors: Michael Dan\n"
console.log(string.replace(/(Title:).*(?=\nAuthors:)/g, '$1 Test'));The pattern matches
(Title:) - Group 1: Title: fixed string.* - the rest of the line, any zero or more chars other than line break chars, CR and LF (we need to consume this text in order to remove it)(?=\nAuthors:) - a positive lookahead that matches a location that is immediately followed with an LF char and Authors: string.See the regex demo.
If there can be a CRLF line ending in your string, you will need to replace (?=\nAuthors:) with (?=\r?\nAuthors:) or (?=(?:\r\n?|\n)Authors:).
You might be better off converting to an object first and then just defining the title property:
let string =
`
Title: Hello World
Authors: Michael Dan
`
const stringLines = string.split('\n');
let stringAsObject = {};
stringLines.forEach(
(line) => {
if (line.includes(':')) {
stringAsObject[line.split(':')[0]] = line.split(':')[1];
}
}
);
stringAsObject.Title = 'NewValue';
You can use replace method like that:
string.replace("Hello World", "Test");
Hello World I need to find it first.
Hello world. I need to find it first and then replace it. This text is always different.I can achieve this without regex. All you need is knowing the index of the string that you need to find.
var original = `
Title: Hello World
Authors: Michael Dan
`;
var stringToFind = "Hello World";
var indexOf = original.indexOf(stringToFind);
original = original.replace(original.substring(indexOf, indexOf + stringToFind.length), "Hey Universe!");
console.log(original)
replace(), you do not need tomatch().string.replace(/(Title:).*(?=\nAuthors:)/gs, '$1Test')can be used here.sflag. Anyway, you need to keep the first and last words.