How to check if bytes variable is empty?
I have a mapping in my smart contract with bytes32 keys and bytes values. How can I check if bytes value exists for specific key?
Mapping is something like this:
mapping(bytes32 => bytes) public Countries;
solidity bytes
asked Jan 12 at 6:34
saman.shahmohamadisaman.shahmohamadi
15010
add a comment |
I have a mapping in my smart contract with bytes32 keys and bytes values. How can I check if bytes value exists for specific key?
Mapping is something like this:
mapping(bytes32 => bytes) public Countries;
solidity bytes
asked Jan 12 at 6:34
saman.shahmohamadisaman.shahmohamadi
15010
add a comment |
I have a mapping in my smart contract with bytes32 keys and bytes values. How can I check if bytes value exists for specific key?
Mapping is something like this:
mapping(bytes32 => bytes) public Countries;
solidity bytes
asked Jan 12 at 6:34
saman.shahmohamadisaman.shahmohamadi
15010
I have a mapping in my smart contract with bytes32 keys and bytes values. How can I check if bytes value exists for specific key?
Mapping is something like this:
mapping(bytes32 => bytes) public Countries;
solidity bytes
solidity bytes
asked Jan 12 at 6:34
saman.shahmohamadisaman.shahmohamadi
15010
asked Jan 12 at 6:34
saman.shahmohamadisaman.shahmohamadi
15010
asked Jan 12 at 6:34
saman.shahmohamadisaman.shahmohamadi
15010
asked Jan 12 at 6:34
saman.shahmohamadisaman.shahmohamadi
15010
asked Jan 12 at 6:34
saman.shahmohamadisaman.shahmohamadi
15010
15010
add a comment |
add a comment |
1 Answer
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You can check it via .length. It will be 0 if it is empty/uninitialised.
Countries[key].length
answered Jan 12 at 6:52
ivicaaivicaa
4,753836
add a comment |
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1 Answer
1
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oldest
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1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
You can check it via .length. It will be 0 if it is empty/uninitialised.
Countries[key].length
answered Jan 12 at 6:52
ivicaaivicaa
4,753836
add a comment |
You can check it via .length. It will be 0 if it is empty/uninitialised.
Countries[key].length
answered Jan 12 at 6:52
ivicaaivicaa
4,753836
add a comment |
You can check it via .length. It will be 0 if it is empty/uninitialised.
Countries[key].length
answered Jan 12 at 6:52
ivicaaivicaa
4,753836
You can check it via .length. It will be 0 if it is empty/uninitialised.
Countries[key].length
answered Jan 12 at 6:52
ivicaaivicaa
4,753836
answered Jan 12 at 6:52
ivicaaivicaa
4,753836
answered Jan 12 at 6:52
ivicaaivicaa
4,753836
answered Jan 12 at 6:52
ivicaaivicaa
4,753836
4,753836
add a comment |
add a comment |
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