JavaScript Tutorial/Development/Error
Catch an error (IE)
<source lang="javascript">
<HTML> <HEAD>
<TITLE>Catch that error!</TITLE>
<SCRIPT> function catchError(errString) {
try {
try {
throw new Error (42, "errString is 42!");
}
catch(e) {
if (e.number == 42)
return (e.description + " Got this one!");
else
throw e;
}
}
catch (e){
return(e.description + " This one not handled here!");
}
} </SCRIPT> </HEAD> <BODY> <FORM name="theForm"> <INPUT type=text name=errText size=40 value="42"> <INPUT type=button
name=btnThrow
value="Catch it!"
onClick="alert(catchError(document.theForm.errText.value));">
</FORM> </BODY> </HTML></source>
Throw out an Error
<source lang="javascript">
<HTML> <HEAD>
<TITLE>Throw that error!</TITLE>
<SCRIPT> function throwError(errString) {
try {
throw new Error (42, errString);
}
catch(e){
alert("Error number: " + e.number + "; Description: " + e.description)
}
} </SCRIPT> </HEAD> <BODY> <FORM name="theForm"> Enter text for the error: <INPUT type=text name=errText size=40> <INPUT type=button name=btnThrow value="Throw it!" onClick="throwError(document.theForm.errText.value);"> </FORM> </BODY> </HTML></source>
Try catch user exception
<source lang="javascript">
<html> <head> <title>Try Catch Example</title> <script type="text/javascript"> function addTwoNumbers(a, b) {
throw new Error("Two numbers are required.");
} try {
result = addTwoNumbers(90);
} catch (oException) {
alert(oException.message);
} </script> </head> <body> </body> </html></source>
Use Error
<source lang="javascript">
<html> <head> <title>Try Catch Example</title> <script type="text/javascript"> function addTwoNumbers(a, b) {
throw new Error("Two numbers are required.");
} try {
result = addTwoNumbers(90);
} catch (oException) {
alert(oException.message);
} </script> </head> <body> </body> </html></source>
