Page 163 - CITS - Computer Software Application -TT

COMPUTER SOFTWARE APPLICATION - CITS

Error Name Description

EvalError An error has occurred in the eval() function

RangeError A number “out of range” has occurred
ReferenceError An illegal reference has occurred

SyntaxError A syntax error has occurred

TypeError A type error has occurred
URIError An error in encodeURI() has occurred

The six different values are described below.
Eval Error
An EvalError indicates an error in the eval() function.

Newer versions of JavaScript do not throw EvalError. Use SyntaxError instead.
Range Error
A RangeError is thrown if you use a number that is outside the range of legal values.
For example: You cannot set the number of significant digits of a number to 500.
Example

let num = 1;
try {
num.toPrecision(500); // A number cannot have 500 significant digits
}

catch(err) {
document.getElementById(“demo”).innerHTML = err.name;
}
Reference Error
A ReferenceError is thrown if you use (reference) a variable that has not been declared:
Example

let x = 5;
try {
x = y + 1; // y cannot be used (referenced)
}
catch(err) {
document.getElementById(“demo”).innerHTML = err.name;
}
Syntax Error
A SyntaxError is thrown if you try to evaluate code with a syntax error.
Example
try {

eval(“alert(‘Hello)”); // Missing ‘ will produce an error
}

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CITS : IT&ITES - Computer Software Application - Lesson 37 - 46