Set Label of Field in Quick Create Form when that quick create form opens from A ribbon button

Hi, 

Please refer to my sample code: 

function onLoad(executionContext){
    var formContext = executionContext.getFormContext();
    var pageContext = Xrm.Utility.getPageContext();
    var isWon = pageContext.input.data.param_won;
    if(isWon) formContext.getControl('actualend').setLabel('Win date');
    else formContext.getControl('actualend').setLabel('Lose date');
}

Also, this function needs to be executed when loading the OpportunityClose entity’s quick creation form.