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Why use call? Can't you directly use the method to import the interface of the contract
2022-02-03 23:18:45 【Q & A of Denglian community】
A call in a smart contract must be a method in a contract , Then import the interface of that contract , If you generate an instance, you can call it directly with the function name , Why use low-level call What about this kind of way ？
Take the answer 1：
The main reason is to get transferFrom To determine whether the transfer is successful .
And because of some transferFrom The implementation of does not follow the standard ERC20 The request returns a value of success . This leads to the use of transferFrom Function cannot get the return value directly .
author[Q & A of Denglian community],Please bring the original link to reprint, thank you.
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