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Unreadable characters in "Input Data" of a Transaction of an Ethereum smart contract

I am working on a blockchain project and I managed to create contracts on Sepolia Testnet. Besides I can call the function from my contract (=read the contract) as well. Bu - here comes the question - when I examine the contract, the "Input Data" of the transaction Hash contains some unreadable characters (when displayed in UTF-8).

Below, I copied the content of an "Input Data" of a transaction of a contract I created :

``@R4aW`ý[P`@Qa(8a(9`@Ra2aZV[`Q` aHaOV[PPa¿V[Ta[a/V[`R` ` `` a}W`UaÄV[`aWQ`ÿUaÄV[`UaÄW[aÃWQU` `a¨V[[PPaÑaÕV[PV[[aîW``UP`aÖV[PV[`aaaÌV[aV[PR` aW`ý[a(aüV[PPPPV[``aAW`ý[QaQ` aòV[PPPPV[`` alW`ý[`QgÿÿÿÿÿÿÿÿaW`ý[aa0V[PPPPV[``@QPgÿÿÿÿÿÿÿÿaÂWaÁaV[[`@RPPV[`gÿÿÿÿÿÿÿÿaçWaæaV[[``P` PPV[`[aWQR` PaÿV[a)W`R[PPPPV[``P`aGW`P[` a[WaZaaV[[PPV[NH{q`R`"`R`$`ý[NH{q`R`A`R`$`ý[aZaÎ`9`óþ``@R4aW`ý[P`6a6W`5`àc+¸åa;WcaËâaYW[`ý[aCauV[`@QaPa¢V[`@Qó[as`6ana(V[aV[[`TaaV[`` ` `@Q`@RR` Ta®aV[aûW`aÐWaTR` aûV[`R` ` [TR`` aÞW`[PPPPPV[`Q` aaV[PPV[Ta)aV[`R` ` `` aKW`UaV[`adWQ`ÿUaV[`UaW[aWQU` `avV[[PPaa£V[PV[[a¼W``UP`a¤V[PV[`aÓaÎaõV[aÄV[PR` aëW`ý[aöaAV[PPPPV[``aW`ý[5a` aÀV[PPPPV[`` a:W`ý[`5gÿÿÿÿÿÿÿÿaTW`ý[a`aþV[PPPPV[`ata%V[a~a0V[Pa` aPV[aaV[PPPPV[`` P`Ra¼aiV[PPPV[``@QPgÿÿÿÿÿÿÿÿaëWaêaäV[[`@RPPV[`gÿÿÿÿÿÿÿÿaWaaäV[[``P` PPV[`QPPV[`R` PPPV[7`RPPPV[`[anWQR` PaSV[a}W`R[PPPPV[``P`aW`P[` a¯Wa®aµV[[PPV[NH{q`R`"`R`$`ý[NH{q`R`A`R`$`ý[```PPVþ¢dipfsX" è¨g§ÑW¼B¶uÛBé`ã¥H?bvÓdsolcC3 Z dppCheck.com Hash Value: de5c87ba4ce169c0590fa40b43e4cea7fefb4c3c48971762843dbc2ad87922d3

The only thing I want to save on the contract is the hash value of a transaction of my application - which comes at the very end of the upper example("dppCheck.com Hash Value: de5c87ba4ce169c0590fa40b43e4cea7fefb4c3c48971762843dbc2ad87922d3").

I searched the resources a lot about this subject but I could not find any information. Please let me know if I need to provide more information in order to let you understand my case.

I want to understand what these unreadable characters are and try to omit them if possible.

Solution

  • Transaction Data payload is usually ABI-encoded arguments for the smart contract.

    • The function name, encoded as function selector (4 bytes)
    • The function arguments, each 32 bytes (remaining bytes)

    You can decode this data by using ABI files that you can download somewhere (Etherscan) or get yourself by remcompiling the original Solidity files.

    Them you can use libraries like Web3.py and Web3.js to decode this payload to human readable form.