JavaScript去除文件名称中的后缀名的多种方法

function removeFileExtension(filename) {
    const lastDotIndex = filename.lastIndexOf('.');
    if (lastDotIndex === -1) {
        return filename; // 没有后缀名，直接返回
    }
    return filename.substring(0, lastDotIndex);
}

// 示例
const filename1 = "document.txt";
const filename2 = "image.jpeg";
const filename3 = "no_extension";

console.log(removeFileExtension(filename1)); // "document"
console.log(removeFileExtension(filename2)); // "image"
console.log(removeFileExtension(filename3)); // "no_extension"

function removeFileExtension(filename) {
    const parts = filename.split('.');
    if (parts.length > 1) {
        parts.pop(); // 移除最后一部分（后缀名）
        return parts.join('.');
    }
    return filename; // 没有后缀名
}

// 示例
console.log(removeFileExtension("photo.jpg")); // "photo"
console.log(removeFileExtension("archive.tar.gz")); // "archive.tar"

function removeFileExtension(filename) {
    return filename.replace(/\.[^/.]+$/, "");
}

// 示例
console.log(removeFileExtension("script.js")); // "script"
console.log(removeFileExtension("config.json")); // "config"

function removeFileExtension(filename) {
    const [name] = filename.split('.').slice(0, -1).concat(filename.split('.').slice(0, -1).length ? [] : [filename]);
    return name || filename;
}

// 简化版本（适用于大多数情况）
function removeFileExtensionSimple(filename) {
    const parts = filename.split('.');
    return parts.length > 1 ? parts.slice(0, -1).join('.') : filename;
}

function removeFileExtensionSafe(filename) {
    // 排除以点开头的隐藏文件（如 .gitignore）
    if (filename.startsWith('.') && filename.split('.').length === 2) {
        return filename;
    }
    
    const lastDotIndex = filename.lastIndexOf('.');
    return lastDotIndex === -1 ? filename : filename.substring(0, lastDotIndex);
}

// 示例
console.log(removeFileExtensionSafe(".gitignore")); // ".gitignore"
console.log(removeFileExtensionSafe("normal.file.txt")); // "normal.file"

function getFileNameWithoutExtension(filename) {
    const lastDotIndex = filename.lastIndexOf('.');
    return lastDotIndex === -1 ? filename : filename.slice(0, lastDotIndex);
}