Allowing Only Certain Numbers and/or Increments of Numbers In Form Field

[Ntrimgs]

I have a form field which only allows increments of 25 to be entered into the form field, but now I need it to also allow the number 0. Here is the existing code:

<input type="text" size="3" onChange="this.value = Math.max(Math.round(parseInt(0 + this.value, 10) / 25) * 25, 50);" name="product_qty" value="50" />';

Anyone know how to make this allow 0??

[xelawho]

what is it supposed to do if the number isn't an increment of 25?

<input type="text" size="3" onfocus="oldval=this.value" onChange="if(this.value%25!=0){this.value=oldval}" name="product_qty" value="50" />

[Ntrimgs]

It rounds up or down to the nearest increment of 25. So if someone types in 60, it'll round down to 50. Unfortunately, if someone types in 0, it rounds up to 25 as it is set now.

[xelawho]

is this what you mean?

<input type="text" size="3" onchange="if(this.value%25!=0){this.value = 25 * Math.round(this.value/25)}" name="product_qty" value="50" />

[Ntrimgs]

is this what you mean?

<input type="text" size="3" onchange="if(this.value%25!=0){this.value = 25 * Math.round(this.value/25)}" name="product_qty" value="50" />

That actually worked great! Thanks.

I hate to push my luck but I have a similar code that allows an increment of 12 as long as it's 12 or 24, and then anything over 25 it rounds up or down to the nearest 25 increment like the other code did. Is there a way to make this allow a zero as well?

<input type="text" size="4" onChange="var n = parseInt(0 + this.value, 10), x = n <= 50 ? 12 : 25; this.value = Math.max(Math.round(n / x) * x, 12);" name="product_qty" value="12" />

[xelawho]

the "purists" will say that you shouldn't be mixing the javascript with the html, but that's your choice:

<input type="text" size="3" onchange="this.value=Number(this.value)<25?12 * Math.round(this.value/12):25 * Math.round(this.value/25)" name="product_qty" value="12" />

I realized the other one can be simplified, btw...

<input type="text" size="3" onchange="this.value = 25 * Math.round(this.value/25)" name="product_qty" value="50" />

[Ntrimgs]

Thanks a ton for all your help!!! I was at my wits end with this. Thanks again!