When I call the approve function of the ERC20 token standard, it asks me to set a custom spending cap, as shown below.
But I need to use the default value every time without clicking "use default." It should always recognize "use default" as default method. How can I do that?
Simple answer, you cannot for good reason.
Find your answer here.
We designed this interface to give you more control and visibility over your token allowances, since you'll be prompted to always input a preferred limit, rather than default to the amount proposed by the dapp (though you can still select this default allowance if you choose).
