當值非常接近時，bytes32 比較返回 true

有這個煩人的問題，其中彼此靠近的 bytes32 在比較時返回 true。

truffle(development)> 0x5b3138302c3132302c3135392c3232332c36342c3135392c36392c323821311a == 0x5b3138302c3132302c3135392c3232332c36342c3135392c36392c323821311c
true

truffle(development)> 0x5b3138302c3132302c3135392c3232332c36342c3135392c36392c323821311a == 0x5b3138302c3132302c3135392c3232332c36342c3135392c36392c323821311d
true

truffle(development)> 0x5b3138302c3132302c3135392c3232332c36342c3135392c36392c32382c322d == 0x5b3138302c3132302c3135392c3232332c36342c3135392c36392c32382c322c
true

truffle(development)> 0x4b3138302c3132302c3135392c3232332c36342c3135392c36392c32382c322d == 0x5b3138302c3132302c3135392c3232332c36342c3135392c36392c32382c322c
false

Am I missing something?
It is affecting my mapping. Using values that are near to each other causes the same result to be returned. 

這是因為 Javascript 使用浮點數來儲存您的數字：

truffle(development)> 0x5b3138302c3132302c3135392c3232332c36342c3135392c36392c32382c322d
4.1247432523778224e+76

truffle(development)> 0x5b3138302c3132302c3135392c3232332c36342c3135392c36392c32382c322c
4.1247432523778224e+76

您想使用 BigNumber 類及其 equals() 函式：

truffle(development)> var a = new web3.BigNumber("0x5b3138302c3132302c3135392c3232332c36342c3135392c36392c32382c322c")
undefined

truffle(development)> var a_again = new web3.BigNumber("0x5b3138302c3132302c3135392c3232332c36342c3135392c36392c32382c322c")
undefined

truffle(development)> var b = new web3.BigNumber("0x5b3138302c3132302c3135392c3232332c36342c3135392c36392c32382c322d")
undefined

truffle(development)> a.equals(b)
false

truffle(development)> a.equals(a_again)
**true**

truffle(development)> a == b
false

truffle(development)> a == a_again
false

引用自：https://ethereum.stackexchange.com/questions/37964