var str = "Is this This?"; //var regex = new RegExp("is", "gi"); var regex = /is/gi; //console.log(regex.test(str)); console.log(regex.exec(str)); //["Is", index: 0, input: "Is this This?"] console.log(regex.exec(str)); //["is", index: 5, input: "Is this This?"] console.log(regex.exec(str)); //["is", index: 10, input: "Is this This?"] console.log(regex.exec(str)); //null console.log(str.match(regex)); //["Is", "is", "is"] console.log(str.replace(regex, "XX")); //"XX thXX ThXX?" console.log(str.search(regex)); // 0, return the first index that found
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App:
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Javascript Regular Expressions: Introduction</title> <style> pre { line-height: 2; } span { background-color: #eee; padding: 1px; outline: 1px solid #999; } </style> </head> <body> <pre></pre> </body> </html>
'use strict'; const output = (str, regex, target) => { target.innerHTML = str.replace(regex, str => `<span>${str}</span>`); } var str = `Is this This?`; //var regex = new RegExp("is", "g"); var regex = /is/gi; output(str, regex, document.querySelector('pre')) // console.log(regex.test(str)); // console.log(regex.exec(str)); // console.log(regex.exec(str)); // console.log(regex.exec(str)); // console.log(regex.exec(str)); // console.log(str.match(regex)); // console.log(str.replace(regex, str => "XX")); // console.log(str.search(regex));
