解释 JavaScript 中正则表达式的“dotAll”标志
dotAll 标志会返回 true 或 false,具体取决于正则表达式中是否设置了 s 标志。
以下是 JavaScript 中用于实现正则表达式 dotAll 标志的代码 −
范例
<!DOCTYPE html> <html lang="en" > <head> <meta charset="UTF-8" /> <meta name="viewport" content="width=device-width, initial-scale=1.0" /> <title>Document</title> <style> body { font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif; } .result { font-size: 20px; font-weight: 500; } </style> </head> <body> <h1>dotAll flag for regular expressions</h1> <div style="color: green;" class="result"></div> <button class="btn">CLICK HERE</button> <h3> Click on the above button to know if s flag has been set in regex or not </h3> <script> let btnEle = document.querySelector(".btn"); let resEle = document.querySelector(".result"); const regex = new RegExp("Hello", "s"); btnEle.addEventListener("click", () => { resEle.innerHTML = "The s flag has been set : " + regex.dotAll; }); </script> </body> </html>
输出
上述代码将生成以下输出 −
点击“单击此处”按钮 −
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