如何在特定子字符串之后替换字符串的一部分

function replaceAfterSubstring(originalString, substring, replacement) {
  // 查找特定子字符串的位置
  var index = originalString.indexOf(substring);
  
  // 如果找到了特定子字符串
  if (index !== -1) {
    // 分割字符串
    var beforeSubstring = originalString.substring(0, index + substring.length);
    var afterSubstring = originalString.substring(index + substring.length);
    
    // 替换部分
    var replacedPart = afterSubstring.replace(/./g, replacement); // 这里使用了正则表达式将所有字符替换为指定字符串
    
    // 拼接字符串
    var finalString = beforeSubstring + replacedPart;
    
    return finalString;
  }
  
  // 如果未找到特定子字符串，则返回原始字符串
  return originalString;
}

// 示例用法
var originalString = "Hello, world! This is a sample string.";
var substring = "world";
var replacement = "*";
var replacedString = replaceAfterSubstring(originalString, substring, replacement);
console.log(replacedString);