lua学习笔记16：table元表详解

标签：lua   元表   

local tab = {}
print(tab.key)

BaseClass = {
	base = 1,
}


DerivedClass = {
	derived = 2,
}
setmetatable(DerivedClass, BaseClass)
print(DerivedClass.base)

print(DerivedClass.base)

BaseClass = {
	base = 1
}
BaseClass.__index = function(tab, key)
	if key == "fun" then
		return 1
	else
		return 0
	end
end


DerivedClass = {
	derived = 2,
}
setmetatable(DerivedClass, BaseClass)
print(DerivedClass.fun)

BaseClass = {
	base = 1,
}
DerivedClass = setmetatable({derived = 2}, {__index = BaseClass})
print(DerivedClass.base)


-------------------------------------------------------------------------
BaseClass = {
	base = 1,
}
DerivedClass = setmetatable({derived = 2}, {__index = function(tab, key)
	if key == "fun" then
		return 1
	else
		return 0
	end
end})
print(DerivedClass.fun)

BaseClass = {
	base = 1,
}
BaseClass.__index = BaseClass


NewElement = {}
BaseClass.__newindex = NewElement


DerivedClass = {
	derived = 2,
}
setmetatable(DerivedClass, BaseClass)


DerivedClass.new = 1


print(BaseClass.new)
print(NewElement.new)
print(DerivedClass.new)

BaseClass = {}
BaseClass.__call = function (BaseClass, a, b)
	return a + b;
end


DerivedClass = {
	derived = 2,
}
setmetatable(DerivedClass, BaseClass)
print(DerivedClass(1, 2))

BaseClass = {}
BaseClass.__tostring = function (BaseClass)
	local str = "-"
	for k, v in pairs(BaseClass) do
		str = str..">"..k..":"..v..""
	end
	return str
end


DerivedClass = {
	className = "DerivedClass",
	derived = 2,
}
setmetatable(DerivedClass, BaseClass)
print(DerivedClass)

lua学习笔记16：table元表详解

标签：lua   元表   

原文地址：http://blog.csdn.net/xufeng0991/article/details/43608713