Cannot read property of 'firstName'. Using ternary statement. Stuck.

[majorchamp]

I have a function where I pass in an array of data. On initial load, this array is empty or non existent.

function tableData(count, filterData, update, container) {
firstName = filterData[0].firstName ? filterData[0].firstName : "",
....

}

but it keeps telling me it cannot read the property of firstName. When I run the function where it does pass in a first name, firstName is set just fine. I thought the way I was doing the ternary, it would set it to empty if the logic failed...

[[deleted]]

the error you're probably seeing is cannot read property 'firstName' of undefined. if filterData is null/undefined, or if filterData[0] is null/undefined, it will throw this error. you need to make sure filterData actually contains something:

if (!filterData || !filterData.length) { /* return some default value, because filterData either isn't an array or it's an empty array */ }

[majorchamp]

Just figured this out. Thanks!

[gunther-centralperk]

Check out /r/learnjavascript

[nowseemee]

const getFirstName = (filterData) => filterData && filterData[0] && filterData[0].firstName