JavaScript default value if undefined | Code
With the Nullish Coalescing Operator, you can set a default value if a value is null or undefined in JavaScript. However, you should be aware… Read More »JavaScript default value if undefined | Code
JS undefined
JavaScript object length undefined | Solution
You will get this error (message in the log) object length undefined in JavaScript if you use the length property in an Object. Use Object.keys(yourObject).length… Read More »JavaScript object length undefined | Solution
JavaScript array length undefined | Code
Objects don’t have a length property, that way most time developers get JavaScript array length undefined error. A simple solution if you know you don’t… Read More »JavaScript array length undefined | Code
JavaScript array is undefined | Example code
Use length property with isArray() method to check an array is undefined in JavaScript. Or do the check for undefined first, array empty or does… Read More »JavaScript array is undefined | Example code
JavaScript undefined property | Variable value
The undefined value is a condition where an expression does not have a correct value. JavaScript undefined property indicates that a variable has not been… Read More »JavaScript undefined property | Variable value
Difference between undefined and null in JavaScript | Example code
Difference between undefined and null is undefined means a variable has been declared but has not yet been assigned a value, where null is an… Read More »Difference between undefined and null in JavaScript | Example code
JavaScript check if undefined | Example code
Use the in operator for a more robust check of variables if undefined or not in JavaScript. Or you can use typeof like this: JavaScript… Read More »JavaScript check if undefined | Example code
JavaScript check if a variable is defined and not empty | Example
Use typeof method with not equal operator to check if a variable is defined and not empty in JavaScript. Or syntax for checking null or… Read More »JavaScript check if a variable is defined and not empty | Example
JavaScript checks if the variable is defined | Example code
Use typeof to check (determine) if the variable is defined or not in JavaScript. The typeof operator can evaluate even an undeclared identifier without throwing… Read More »JavaScript checks if the variable is defined | Example code
JavaScript if not undefined or null | Example code
Use the qualities of the abstract equality operator to find the undefined or null variable in JavaScript. Therefore we use == and only compare to… Read More »JavaScript if not undefined or null | Example code