String Manipulation Question

[Mighty]

Guys,

This one is probably quite easy but I just don't know how to do it. This is basically what I want to do ( in rough pseudocode ).

A string and a character are passed to this js function:

function validNumber(string, firstChar) {

if (first char of string == firstChar) {
verify that from second char of string to end is a number
}
else {
verify that string is a number
}
}

I know that I can use isNan to verify whether or not a variable is numeric or not. It's just the fact that I have to check the first character. Can you please tell me if this can easily be done. Mise Le Meas,

Mighty

 

[Klae]

you could try,

function validNumber(stringObj, firstChar)
{
 if (stringObj.substr(0, 1) == firstChar)
 {
   code to run....
 }
 else
 {
  other code to run...
 }
}

Is this what you meant?

 

[harmmeijer]

The command used to check a certain caracter in a string is :
Yourvar.charAt(0)
The first caracter is 0 the last caracter is:
Yourvar.length - 1
You can check the following script below:

<script>
function checknr() {
nrvar = document.test.nrstr.value
i1 = 0;
while(i1 < nrvar.length) {
//According to isNaN the space is allso a number
if(isNaN(nrvar.charAt(i1)) || nrvar.charAt(i1) == &quot; &quot {
alert(&quot;Please enter a number value&quot
break;
}
i1++
}
}
</script>

<form name = &quot;test&quot;>
<input type = &quot;text&quot; name = &quot;nrstr&quot;><br>
<input type=&quot;button&quot; name=&quot;but&quot; value=&quot;klick here&quot; onclick=&quot;checknr()&quot;><br>
</form>