function isNumber(num){
if( !isNaN(num.value) && (num.value != "")){
return true;
} else {
return false;
}
isNumber (5) returns false I don"t know what"s wrong
"undefined"
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what does the code circled in the following picture mean? ...
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How does the code return only the result after the last asynchronous operation in the for loop is completed as shown in the figure? Please stop by and give me a hand. ...