To check whether user has entered has enter only blank spaces or some text.

[Sudhir123]

Hi..
I need to find out whether user has entered only black spaces or some text which might have some spaces..
But i more interested to check for blanck spaces (by spacebar key).
how i will find out this. I used trim function, but it trims text also..i m using my own framework which i built for application.
Plz suggest me somthing..
following functions are not working.
element.length==0 and
element==null

[Dormilich]

@Sudhir123
then there’s something wrong with your trim function. you may work around it with String.replace().

note: Firefox 3.5 brings its own trim method.

[gits]

show your trim function ... normally you trim the value and then check its length ... that is reliable ... but depends on a correct trim function. to check a value that is not empty but just contains whitespaces you could even use a regExp like this:

var s = '        ';
 
alert(/^[ ]+$/.test(s));

kind regards

PS: :) ahhh ... one minute late ... Dormilich's replace()-hint would work too when you want to work around your trim-function ...

[Sudhir123]

Hi guys..
Thanks for ur replies...!! These r really worthful...!!
i found another solution...
I counted blank spaces and put validation for it.!!

                            var c=0;
                if (element) {
                      for (var i=0; i<element.length; i++) {
                            if (element.charAt(i) == " ") {
                              c++
                             }
                             }
                             } 
    if(element.length==c)
      return xyz. // according to ur need..!!

[Dormilich]

@Sudhir123
IMHO a solid trim function is a better choice.

I thought of something like

if ("function" != typeof String.trim)
{
    String.prototype.trim = function()
    {
        return this.replace(/^\s*/, "").replace(/\s*$/, "");
    }
}

// use like
var txt = input.value.trim();

[gits]

@Dormilich
much better ... no question :) ... as a rule of thumb is that loops are to avoid wherever it is possible ...

kind regards