基于逻辑运算的简单权限系统(实现) JS 版

  作者: slightboy, 时间: 2006-10-17

  此篇为 JS 实现版本, 以前作已交待原理 故不在此多做解释

  如需原理介绍 请查看 VBS 版.

  var PermissionType =

  {

  Read : 1,

  Write : 2,

  Delete : 4

  }

  function PermissionSetComponent(value)

  {

  this.Value = value;

  this.getRead = function()

  {

  return this.getValue(PermissionType.Read);

  }

  this.setRead = function(value)

  {

  this.setValue(PermissionType.Read, value);

  }

  this.Read = function()

  {

  if (arguments.length > 0)

  this.setValue(PermissionType.Read, arguments[0]);

  else

  return this.getValue(PermissionType.Read);

  }

  this.Write = function()

  {

  if (arguments.length > 0)

  this.setValue(PermissionType.Write, arguments[0]);

  else

  return this.getValue(PermissionType.Write);

  }

  this.Delete = function()

  {

  if (arguments.length > 0)

  this.setValue(PermissionType.Delete, arguments[0]);

  else

  return this.getValue(PermissionType.Delete);

  }

  this.getValue = function(permissionType)

  {

  return (this.Value & permissionType) == permissionType;

  }

  this.setValue = function(permissionType, value)

  {

  if (value)

  this.Value |= permissionType;

  else

  this.Value &= ~permissionType;

  }

  }

  var PermissionSet = new PermissionSetComponent(0);

  w("Read:");

  PermissionSet.Read(false);

  w(PermissionSet.Value +" "+ PermissionSet.Read());

  PermissionSet.Read(true);

  w(PermissionSet.Value +" "+ PermissionSet.Read());

  w("Write:");

  PermissionSet.Write(false);

  w(PermissionSet.Value +" "+ PermissionSet.Write());

  PermissionSet.Write(true);

  w(PermissionSet.Value +" "+ PermissionSet.Write());

  w("Delete:");

  PermissionSet.Delete(false);

  w(PermissionSet.Value +" "+ PermissionSet.Delete());

  PermissionSet.Delete(true);

  w(PermissionSet.Value +" "+ PermissionSet.Delete());

  function w(o)

  {

  Response.Write(o +"<br />");

  }

  注: 红色部分为 java 风格写法 不是本例所必须.

  只是做一个展示, 如果你比较喜欢 java 风格也可以选择这种写法.