智能合约开发常用方法

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ADDR_TYPE

账户格式类型

ADDR_TYPE = {
    REGID  = 1,
    BASE58 = 2
  }

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OP_TYPE

账户操作类型定义

OP_TYPE = {
    ADD_FREE    = 1,
    SUB_FREE    = 2
  }

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TableIsNotEmpty

判断传入的table是否为非空

Code sample

TableIsNotEmpty = function (t)
    return _G.next(t) ~= nil
end

Parameters

parameter	type	example
t	table	{0x01,0x23}

Returns

true :不为空 flase : 为空

---

Unpack

从第i个元素开始，遍历并输出table数组所有元素

Code sample

Unpack = function (t,i)
    i = i or 1
    if t[i] then
      return t[i], Unpack(t,i+1)
    end
end

Parameters

parameter	type	example
t	table	{0x01,0x23}
i （optional）	Number	5 (Default:1)

Returns

table数组所有元素

---

GetContractTxParam

获取合约内容

Code sample

GetContractTxParam = function (startIndex, length)
    assert(startIndex > 0, "GetContractTxParam start error(<=0).")
    assert(length > 0, "GetContractTxParam length error(<=0).")
    assert(startIndex+length-1 <= #contract, "GetContractTxParam length ".. length .." exceeds limit: " .. #contract)

    local newTbl = {}
    local i = 1
    for i = 1,length do
      newTbl[i] = contract[startIndex+i-1]
    end
    return newTbl
  end

Parameters

parameter	type	example
startIndex	Number	2
length	Number	5

Returns

目标合约内容

---

MemIsEqual

比较t1和t2是否相等

Code sample

MemIsEqual = function (t1,t2)
    assert(TableIsNotEmpty(t1), "t1 is empty")
    assert(TableIsNotEmpty(t2), "t2 is empty")

    if(#t1 ~= #t2) then
      return false
    end

    local i = 1
    for i = #t1,1,-1 do
      if t1[i] ~= t2[i] then
        return false
      end
    end
    return true
end

Parameters

parameter	type	example
t1	table	{0x01,0x02,0x03}
t2	table	{0x01,0x02,0x03}

Returns

true :相等 flase : 不相等

---

GetByte

获取字符串的byte table数组

Code sample

GetByte = function(param)
  return {string.byte(param,1,string.len(param))}
end

Parameters

parameter	type	example
param	String	"admin"

Returns

转换后的table数组

---

Serialize

table数组转换为字符串或者hex

hex = true : 转换为hex

hex = false : 转换为字符串

Code sample

Serialize = function(obj, hex)
    local lua = ""
    local t = type(obj)

    if t == "table" then
    for i=1, #obj do
      if hex == false then
        lua = lua .. string.format("%c",obj[i])
      elseif hex == true then
        lua = lua .. string.format("%02x",obj[i])
      else
        error("index type error.")  
      end
    end
    elseif t == "nil" then
        return nil
    else
        error("can not Serialize a " .. t .. " type.")
    end

    return lua
end

Parameters

parameter	type	example
obj	table	{0x01,0x02,0x03}
hex	boolean	false

Returns

转换后的字符串或者hex - String

---

Main

智能合约的入口函数 * Main 方法是智能合约调用的入口； * 当调用智能合约时，table类型的contract会作为全局变量传入。 * 根据字节数组里面的数组第二个字段判定，应该走到哪一个不同的方法

Main = function()
--  for i=1, #contract do
--  print(i, contract[i])
-- end
  assert(#contract >=4, "Param length error (<4): " ..#contract )
  assert(contract[1] == 0xf0, "Param MagicNo error (~=0xf0): " .. contract[1])

  if contract[2] == 0x17 then
   -- 调用方法

  else
    error('method# '..string.format("%02x", contract[2])..' not found')
  end

end

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