TRIPAGO.sol is a fixed supply contract with a fixed supply of 1000000000 that are initially assigned to the owner of the contract. The Contract is based on ERC20 Token Standard.
TRIPAGO ICO contract.
Deploy the above TRIPAGO.sol smart contract and obtain its address. The address which deployed the Smart Contract becomes the Owner of the Smart Contract.
To check the token balance of token holder, balanceOf() function needs to be used. For example, assume the TRIPAGO contract has two token holders:
- 0x111 with a balance of 50 TPG
- 0x222 with a balance of 100 TPG
The balanceOf() will return following values:
- balanceOf(0x111) will return 50
- balanceOf(0x111) will return 100
To transfer TPG tokens to different address, transfer() function needs to be used.
For example,If 0x111 wants to transfer 10 TPG to 0x222, 0x111 will execute the function:
- transfer(0x222, 10)
The balanceOf() will now return following values:
- balanceOf(0x111) will return 40
- balanceOf(0x222) will return 110
If 0x222 wants to authorise 0x111 to transfer some tokens on his behalf, then 0x222 will execute the approve() function
For example,If 0x222 wants to approve 30 TPG to 0x111, 0x222 will execute the function:
- approve(0x111, 30)
The approve data structure will now contain the following information:
- allowed[0x222][0x111] = 30
Now, if 0x111 wants to later transfer some tokens from 0x222 to itself, then 0x111 will execute transferFrom() function
For example, if 0x111 wants to transfer 20 TPG to itself, 0x111 will execute function:
- transferFrom(0x222, 0x111, 20)
The balances data structure will contain the following information:
- balances[0x111] = 60
- balances[0x222] = 90
And, approve data structure will now contain the following information:
- allowed[0x222][0x111] = 10
Thus, 0x111 can still spend 10 TPG from 0x222,
The balanceOf() will now return following values:
- balanceOf(0x111) will return 60
- balanceOf(0x222) will return 90
The above two addresses(0X111, 0X222) taken in Example are not Valid Ethereum Addresses, to make transaction you need to have a valid Ethereum Address.