JavaScript Throw Statement
The throw statement allows you to create an exception.
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
The example below determines the value of a variable called x. If the value of x is higher than 10, lower than 0,
or not a number, we are going to throw an error.
The error is then caught by the catch argument and the proper error message is displayed:
Example
<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";
}
else if(isNaN(x))
{
throw "Err3";
}
}
catch(er)
{
if(er=="Err1")
{
alert("Error! The value is too high");
}
if(er=="Err2")
{
alert("Error! The value is too low");
}
if(er=="Err3")
{
alert("Error! The value is not a number");
}
}
</script>
</body>
</html> |
Try it yourself »
|
Need an easy way to get data into XML, or transform XML to another format?
MapForce lets you map XML data to/from any combination of XML, database, flat file, Excel 2007, XBRL, or Web services data.
Then it transforms data instantly or auto-generates royalty-free data integration code for recurrent conversions.
New features in Version 2010!
Download a free, fully functional 30-day trial to experience the following features:
- Easy-to-use, graphical data mapping interface
- Instant data transformation
- XSLT 1.0/2.0 and XQuery code generation
- Java, C#, and C++ code generation
- Advanced data processing functions
- Support for all major relational databases including SQL Server, IBM DB2, Oracle, and more
- Visual Studio & Eclipse integration
Download a fully-functional trial today!
|
|
|
|
