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Simple Ethereum ERC20 token php library

This library provides simple way to interact with Ethereum ERC20 token.
By default, supports all ERC20 Standard functions (like balanceOf, transfer, transferFrom, approve, allowance, decimal, name, ...) also can be extends to support other contracts as well.

基于lessmore92/php-erc20库做了些修改

Installation

composer require cqtop/eth-nano-erc20

Usage

There are two ways to use:

1- Make a new class for your token and specified their functions

2- Use general class with all standard functions

See below to find out more

1-Make a new class for your token

Simply create a new class inherits from \Lessmore92\Ethereum\Foundation\StandardERC20Token

in below sample we create a new class for Tether (USDT)

Then for use create new instantiate from your class and

2- Use general class

Connection Timeout

Connection timeout can be set by last parameter of token class

OR

Ethereum RPC Client

For connect to Ethereum blockchain you need an Ethereum node; Infura is a simple and fast solution, however you can launch you Geth node

ERC20 Token transferFrom

ERC20 transaction fee needs to be paid in ETH. In some situation your app needs to pay this fee behalf of user.
Suppose, user A have a key pair (private, public) and all their transaction is limited to usdt. User A needs to send 10 usdt, but he/she haven't ETH to pay transaction fee.
In these cases your app should pay fee behalf of users.
transferFrom is a good solution in these cases.

transferFrom Flow:

1.First, Using approve method to grant permission to a delegator.
2.Then, Using transferFrom method to make transaction behalf of user.

In Action

allowance to check how much transferFrom remain

$remain = $token->allowance($owner_address, $myapp_address);

Notices:
approve method not need to be used on every transaction.
To revoke transferFrom permission call $token->approve($owner_address, $myapp_address, 0) by amount 0.