convert string to integer using Javascript and Jquery

Question

I need one help.I have one value ('i.e-001') which datatype is varchar and i convert this into integer and then want to add 1 at each time DB entry.I did something like below.

var newcode=parseInt(response.data.code)+1;

Here response.data.code contains the code 001 and its coming from DB.first user is fetching the latest code(i.e-001) from db and increment by 1 then storing in the DB.In this case i am getting newcode value is 2 but I should get 002,'003',..so on.Please help me.

• guest271314: "but I should get 002" 002 is not a valid js integer
• Yeldar Kurmangaliyev: Why are you doing this manually? It will create many, many problems.
• Eric Guan: 2 = 002. What you want is a formatted string.
• Achu: Why you want 2 as 002 what was the purpose ?
• Mat Taylor: is there a reason you are not using just a good old basic int with auto increment turned on for an ID?

Answer 1

Use a small function:

<script>
function pad(n, width, z) {
 z = z || '0';
 n = n + '';
 return n.length >= width ? n : new Array(width - n.length + 1).join(z) + n;
}
var len = response.data.code.length;
var newcode=parseInt(response.data.code)+1;
alert(pad(newcode, len));
</script>

JSFiddle

• satya: @ MyWay : when response.data.code is 011 it is giving the output 010 and also 4 digit case its giving the different output.

Answer 2

After incrementing do the padding again

var originalLength = response.data.code.length; //to ensure that new number is of same length
var newcode=parseInt(response.data.code)+1;
while( newcode.toString().length < originalLength ) //assuming that you want length 3
{
 newcode= "0" + newcode;
}
alert( newcode );

• Sam: Why not just do newcode.toString() in the while loop instead of newcode+""? They both work the same but toString would make it much more readable.
• gurvinder372: @Sam yes it will, making that change. Thanks

Answer 3

When you do parseInt Javascript removes 00 before the number and you get exact 1.

So if you add 1 you get 2.

If you want to get 002 you should try

var newcode= '00'+parseInt(response.data.code)+1;

For 10 digits just loop it:

for(var i=0; i<10-newcode.length; i++){
 newcode = '0'+newcode;
}

But the best solution was provided by YeldarKurgmangaliev.

It's terrible mistake to generate ID in jQuery, do it in database.

• Yeldar Kurmangaliyev: If it was 017, it will become 0018 which seems to be incorrect.
• satya: @YeldarKurmangaliyev :Good catch.so what is the perfect solution.
• Yeldar Kurmangaliyev: @satya The perfect solution is to stop doing this manually and let your DB use integer auto-increment.
• Sanat Serikuly: @satya how much digits you want to have?
• satya: @SanatSerikuly:For now its 10

Answer 4

Try using String.prototype.replace() with RegExp /(\d+$)/ to match digit characters

var str = "i.e-009";
str = str.replace(/(\d+$)/, function(match) {
 var n = Number(match) + 1, len = String(n).length
 // if `n` equals `9` , return `"i.e-009"`
 // if `n` equals `10`, return `"i.e-010"`
 // if `n` equals `100` rerurn `"i.e-100"`
 , res = len === 1 ? "00" : len === 2 && "0" || len === 3 && "";
 return res + n
});
console.log(str)