JavaScript Throw Statement
The throw statement allows you to create an
exception.
Examples
The throw statement
How to use the throw statement.
The Throw Statement
The throw statement allows you to create an exception. If you use this
statement together with the try...catch statement, you can control program
flow and generate accurate error messages.
Syntax
The exception can be a string, integer, Boolean or an object.
Note that throw is written in lowercase letters. Using uppercase
letters will generate a JavaScript error!
Example 1
The example below determines the value of a variable called x. If the value
of x is higher than 10 or lower than 0 we are going to throw an error. The error is then caught by the catch argument and the proper
error message is displayed:
<html>
<body>
<script type="text/javascript">
var x=prompt("Enter a number between 0 and 10:","");
try
{
if(x>10)
throw "Err1";
else if(x<0)
throw "Err2";
}
catch(er)
{
if(er=="Err1")
alert("Error! The value is too high");
if(er == "Err2")
alert("Error! The value is too low");
}
</script>
</body>
</html>
|
|
|
|