Limit the Input field to Have only 1 + sign or - sign in it.

[wrighterb]

I want to Limit the Input field to Have only 1 + sign or - sign in it.

Any idea?

 

[BabyJeffy]

You could attach an onkeyup event to the input that triggers a function every time a key is released in the input. The function could be just a regular expression that replaces the value of the input with any unwanted extra + characters removed.

Cheers,
Jeff

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What is Javascript? FAQ216-6094

 

[monksnake]

Without being more specific on the regular expression, I'm not sure how to do it using one.

You can loop through each character of the input string and check the character with a charAt function. Keep track if you have one or more + or - signs, if more than one, alert the user to remove them.

<.

 

[wrighterb]

I have this as my onkeyup function. So you say a loop to it?


function clearChar() {
document.adjustment.adjustAmount.value=filterNum(document.adjustment.adjustAmount.value)
function filterNum(str) {
re = /[^0-9.+-}]/g
return str.replace(re, "");
}
}