[學習筆記] 智能合約 20190423 by deanliu

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cn · @deanliu ·
$18.14
[學習筆記] 智能合約 20190423
![](https://steemitimages.com/DQmebRJap3xUvmsBNapMqb528wxhvYPiDzbeH8gYdm6oTEA/image.png)
<sub>*source: http://ggllaw.net/areas-of-practice/*</sub>

最近，因為某些因素，想要更進一步多了解智能合約的運行實際情況，想起往年的文章，回頭找出這兩篇合作文章 (由失聯已久的 @antonsteemit執筆)

[DA-ChainTalk #1 — State，從宏觀到微觀：以太坊如何將智能合約帶入區塊鏈世界](https://steemit.com/da-chaintalk/@deanliu/state)
[DA-ChainTalk #3 — 智能合約之前世今生](https://steemit.com/da-chaintalk/@deanliu/da-chaintalk-3)

再讀一次，才發現自己當時其實沒有完全吸收，事隔一年再看，還是頗有收穫。不過，這樣的理解程度，還不能滿足我的需求，所以，去找了一位作開發的朋友，問他一下，這是最快的方式。

果然，寫代碼的朋友，頭腦都蠻清楚的，他跟我聊了十多分鐘，我收穫蠻大的。如果要自己看書來理解，恐怕是非常困難的。


以下，我把我學習到的基本概念，整理出來。也可能因為我理解錯誤而有錯，有專業的讀者們，歡迎指正我，繼續教導我更多關於智能合約的知識吧！^^

關於智能合約（smart contracts）

* 智能合約，可以被視為在區塊鏈上執行的程式，但比起一般程式，智能合約所受到的制約更多，所能達成的功能也比較有限。

* 智能合約的佈署(deploy)，是透過一個EOA帳戶來上傳區塊鏈，把compile過的Solidity原始碼，記錄到一個智能合約帳戶裡去。

* 每個智能合約內可以有各種寫好的functions以及variables，variables的state可以更新，但智能合約本身結構，在上傳後就是不可更改的。

* 智能合約的地址，就是其上傳的那一個區塊地址，後面呼叫此合約，就會到此一地址來取得執行代碼。

* 智能合約的執行是必須依靠外界的觸發，且其執行具有atomic的概念，亦即所有程式都在這一次執行完成，完成後的更新狀態，紀錄為transaction

* 每個Ethereum礦工執行的結果是否符合該合約應該有的結果，可以輕易由其他礦工驗證，正如比特幣區塊鏈上，交易的結果是否正確，可以輕易由後續礦工所驗證。

* 因此，智能合約無法做到諸如：每個週一定時，自動地，由帳戶A轉帳1 Ether到帳戶B，這樣的自動化程序。

如果大家有推薦什麼好的文章連結，可以深入淺出地解釋智能合約的運作（不能太淺，但也不能技術性），請多多推薦給我吧！

![danbo-2495978_1280.jpg](https://steemitimages.com/DQmPACz2EHrzRFo6hguBVa63YC49YLSkYYQqysKeNeGvtuo/danbo-2495978_1280.jpg)
<sub> Image Source: pixabay</sub>
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@partiko · 
Thank you so much for participating in the Partiko Delegation Plan Round 1! We really appreciate your support! As part of the delegation benefits, we just gave you a 3.00% upvote! Together, let’s change the world!
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@icebing925 · 
突然想起去年跟着你的post学python，结果学到一半放弃了😂

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@deanliu · 
呵呵，別提了，我自己都沒學好呢，現在全部都忘了.... >_<
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@steem-plus ·
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@steem-ua · 
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@dailychina ·
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Congratulations! This post has been selected by @justyy as today's (2019-04-24)  [【Good Posts】](https://steemit.com/cn/@justyy/--daily-cn-updates-cncnpower-downyy2019-04-24), Steem On!  Reply to this message in 24 hours to get rewards. Upvote this comment to support the @dailychina and increase your future rewards! ^_^

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