Throwing String Exceptions : Error Exceptions « Development « JavaScript DHTML






  1. JavaScript DHTML
  2. Development
  3. Error Exceptions

Throwing String Exceptions

<HTML>
<HEAD>
<TITLE>Throwing a String Exception</TITLE>
<SCRIPT LANGUAGE="JavaScript">
var letters = new Array("A","B","C","D","E")
function getLetter(fld) {
    try {
        var inp = parseInt(fld.value, 10)
        if (isNaN(inp)) {
            throw "Entry was not a number."
        }
        if (inp < 1 || inp > 5) {
            throw "Enter only 1 through 5."
        }
        fld.form.output.value = letters[inp-1]
    }
    catch (e)  {
        alert(e)
        fld.form.output.value = ""
        fld.focus()
        fld.select()
    }
}
</SCRIPT>
</HEAD>
<BODY>
<H1>Throwing a String Exception</H1>
<HR>
<FORM>
Enter a number from 1 to 5: 
<INPUT TYPE="text" NAME="input" SIZE=5>
<INPUT TYPE="button" VALUE="Get Letter" onClick=getLetter(this.form.input)>
Matching Letter is:<INPUT TYPE="text" NAME="output" SIZE=5>
</FORM>
</BODY>
</HTML>








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3.Catching an Error
4.Controlling Script Errors
5.An Exception Handling Example
6.Nested Exception Handling (This script only works with Internet Explorer 5, Navigator 6, or later browsers)
7.Using the onError Event Handler
8.Throwing an Error Object Exception
9.A Custom Object Exception