Can you send a token and get ether back?
If a user sends a token, let's call it ABC, to the contract that issued that token, can the contract send back ether to the user?
solidity tokens
edited Nov 12 '18 at 14:01
Paul Berg
1,547423
asked Nov 12 '18 at 11:50
chrisfuturechrisfuture
61
add a comment |
If a user sends a token, let's call it ABC, to the contract that issued that token, can the contract send back ether to the user?
solidity tokens
edited Nov 12 '18 at 14:01
Paul Berg
1,547423
asked Nov 12 '18 at 11:50
chrisfuturechrisfuture
61
add a comment |
If a user sends a token, let's call it ABC, to the contract that issued that token, can the contract send back ether to the user?
solidity tokens
edited Nov 12 '18 at 14:01
Paul Berg
1,547423
asked Nov 12 '18 at 11:50
chrisfuturechrisfuture
61
If a user sends a token, let's call it ABC, to the contract that issued that token, can the contract send back ether to the user?
solidity tokens
solidity tokens
edited Nov 12 '18 at 14:01
Paul Berg
1,547423
asked Nov 12 '18 at 11:50
chrisfuturechrisfuture
61
edited Nov 12 '18 at 14:01
Paul Berg
1,547423
asked Nov 12 '18 at 11:50
chrisfuturechrisfuture
61
edited Nov 12 '18 at 14:01
Paul Berg
1,547423
edited Nov 12 '18 at 14:01
Paul Berg
1,547423
edited Nov 12 '18 at 14:01
Paul Berg
1,547423
1,547423
asked Nov 12 '18 at 11:50
chrisfuturechrisfuture
61
asked Nov 12 '18 at 11:50
chrisfuturechrisfuture
61
asked Nov 12 '18 at 11:50
chrisfuturechrisfuture
61
61
add a comment |
add a comment |
2 Answers
2
active
oldest
votes
Yes, for example:
contract ABCToken
function sell(uint abcAmount) public
uint ethAmount = myFunc(abcAmount);
msg.sender.transfer(ethAmount);
Of course, you probably want to make sure that this user (msg.sender) owns the specified amount of ABC tokens...
answered Nov 12 '18 at 12:20
goodvibrationgoodvibration
3,2301821
add a comment |
Adding to goodVibration's answer, you want to make sure the user actually sent what they say they sent.
contract ABCToken
function sell(uint abcAmount) public
require(token.transferFrom(msg.sender, address(this), abcAmount));
uint ethAmount = myFunc(abcAmount);
msg.sender.transfer(ethAmount);
Transfer from requires the sender to first send an approve() to the token contract to set an allowance the above function can use to retrieve the user's tokens. The 2-step process is usually coordinated client-side or in another contract.
Hope it helps.
answered Nov 12 '18 at 14:45
Rob Hitchens B9labRob Hitchens B9lab
26.6k64480
1
Thanks. Risk of scribbling it up freestyle. Fixed.
– Rob Hitchens B9lab
Nov 12 '18 at 15:57
add a comment |
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2 Answers
2
active
oldest
votes
2 Answers
2
active
oldest
votes
active
oldest
votes
active
oldest
votes
Yes, for example:
contract ABCToken
function sell(uint abcAmount) public
uint ethAmount = myFunc(abcAmount);
msg.sender.transfer(ethAmount);
Of course, you probably want to make sure that this user (msg.sender) owns the specified amount of ABC tokens...
answered Nov 12 '18 at 12:20
goodvibrationgoodvibration
3,2301821
add a comment |
Yes, for example:
contract ABCToken
function sell(uint abcAmount) public
uint ethAmount = myFunc(abcAmount);
msg.sender.transfer(ethAmount);
Of course, you probably want to make sure that this user (msg.sender) owns the specified amount of ABC tokens...
answered Nov 12 '18 at 12:20
goodvibrationgoodvibration
3,2301821
add a comment |
Yes, for example:
contract ABCToken
function sell(uint abcAmount) public
uint ethAmount = myFunc(abcAmount);
msg.sender.transfer(ethAmount);
Of course, you probably want to make sure that this user (msg.sender) owns the specified amount of ABC tokens...
answered Nov 12 '18 at 12:20
goodvibrationgoodvibration
3,2301821
Yes, for example:
contract ABCToken
function sell(uint abcAmount) public
uint ethAmount = myFunc(abcAmount);
msg.sender.transfer(ethAmount);
Of course, you probably want to make sure that this user (msg.sender) owns the specified amount of ABC tokens...
answered Nov 12 '18 at 12:20
goodvibrationgoodvibration
3,2301821
answered Nov 12 '18 at 12:20
goodvibrationgoodvibration
3,2301821
answered Nov 12 '18 at 12:20
goodvibrationgoodvibration
3,2301821
answered Nov 12 '18 at 12:20
goodvibrationgoodvibration
3,2301821
3,2301821
add a comment |
add a comment |
Adding to goodVibration's answer, you want to make sure the user actually sent what they say they sent.
contract ABCToken
function sell(uint abcAmount) public
require(token.transferFrom(msg.sender, address(this), abcAmount));
uint ethAmount = myFunc(abcAmount);
msg.sender.transfer(ethAmount);
Transfer from requires the sender to first send an approve() to the token contract to set an allowance the above function can use to retrieve the user's tokens. The 2-step process is usually coordinated client-side or in another contract.
Hope it helps.
answered Nov 12 '18 at 14:45
Rob Hitchens B9labRob Hitchens B9lab
26.6k64480
1
Thanks. Risk of scribbling it up freestyle. Fixed.
– Rob Hitchens B9lab
Nov 12 '18 at 15:57
add a comment |
Adding to goodVibration's answer, you want to make sure the user actually sent what they say they sent.
contract ABCToken
function sell(uint abcAmount) public
require(token.transferFrom(msg.sender, address(this), abcAmount));
uint ethAmount = myFunc(abcAmount);
msg.sender.transfer(ethAmount);
Transfer from requires the sender to first send an approve() to the token contract to set an allowance the above function can use to retrieve the user's tokens. The 2-step process is usually coordinated client-side or in another contract.
Hope it helps.
answered Nov 12 '18 at 14:45
Rob Hitchens B9labRob Hitchens B9lab
26.6k64480
1
Thanks. Risk of scribbling it up freestyle. Fixed.
– Rob Hitchens B9lab
Nov 12 '18 at 15:57
add a comment |
Adding to goodVibration's answer, you want to make sure the user actually sent what they say they sent.
contract ABCToken
function sell(uint abcAmount) public
require(token.transferFrom(msg.sender, address(this), abcAmount));
uint ethAmount = myFunc(abcAmount);
msg.sender.transfer(ethAmount);
Transfer from requires the sender to first send an approve() to the token contract to set an allowance the above function can use to retrieve the user's tokens. The 2-step process is usually coordinated client-side or in another contract.
Hope it helps.
answered Nov 12 '18 at 14:45
Rob Hitchens B9labRob Hitchens B9lab
26.6k64480
Adding to goodVibration's answer, you want to make sure the user actually sent what they say they sent.
contract ABCToken
function sell(uint abcAmount) public
require(token.transferFrom(msg.sender, address(this), abcAmount));
uint ethAmount = myFunc(abcAmount);
msg.sender.transfer(ethAmount);
Transfer from requires the sender to first send an approve() to the token contract to set an allowance the above function can use to retrieve the user's tokens. The 2-step process is usually coordinated client-side or in another contract.
Hope it helps.
answered Nov 12 '18 at 14:45
Rob Hitchens B9labRob Hitchens B9lab
26.6k64480
edited Nov 12 '18 at 15:57
answered Nov 12 '18 at 14:45
Rob Hitchens B9labRob Hitchens B9lab
26.6k64480
answered Nov 12 '18 at 14:45
Rob Hitchens B9labRob Hitchens B9lab
26.6k64480
answered Nov 12 '18 at 14:45
Rob Hitchens B9labRob Hitchens B9lab
26.6k64480
26.6k64480
1
Thanks. Risk of scribbling it up freestyle. Fixed.
– Rob Hitchens B9lab
Nov 12 '18 at 15:57
add a comment |
1
Thanks. Risk of scribbling it up freestyle. Fixed.
– Rob Hitchens B9lab
Nov 12 '18 at 15:57
1
1
Thanks. Risk of scribbling it up freestyle. Fixed.
– Rob Hitchens B9lab
Nov 12 '18 at 15:57
Thanks. Risk of scribbling it up freestyle. Fixed.
– Rob Hitchens B9lab
Nov 12 '18 at 15:57
add a comment |
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