js以字符串结尾

let str = "Hello, world!";
console.log(str.endsWith("world!")); // 输出: true
console.log(str.endsWith("World!")); // 输出: false，因为区分大小写

// 验证文件扩展名
function isImageFile(filename) {
    return filename.endsWith('.jpg') || filename.endsWith('.png') || filename.endsWith('.gif');
}

console.log(isImageFile("photo.jpg")); // 输出: true
console.log(isImageFile("document.pdf")); // 输出: false

// URL验证
function isSecureUrl(url) {
    return url.endsWith('https://');
}

console.log(isSecureUrl("https://example.com")); // 输出: true
console.log(isSecureUrl("http://example.com")); // 输出: false

let str = "Hello, World!";
console.log(str.toLowerCase().endsWith("world!")); // 输出: true

let emptyStr = "";
console.log(emptyStr.endsWith("")); // 输出: true，因为空字符串以空字符串结尾
console.log(emptyStr.endsWith("a")); // 输出: false

if (!String.prototype.endsWith) {
    String.prototype.endsWith = function(searchString, position) {
        var str = this.toString();
        if (position === undefined || position > str.length) {
            position = str.length;
        }
        position -= searchString.length;
        var lastIndex = str.indexOf(searchString, position);
        return lastIndex !== -1 && lastIndex === position;
    };
}