如何使用Jquery或javascript检查输入的值是否存在

Question

I have one textbox and one button and on button I have written below code. problem is suppose first I have entered in textbox 10 than its worked but when another time I enter 10 than also it prints value is not in array. so pls help me whats the issue...

 jQuery(document).ready(function() { jQuery("#mybutton").live('click',function () { var sel_fam_rel=jQuery("#my_textbox").val(); var ids = []; code =sel_fam_rel; if($.inArray(code,ids) >= 0) { alert("Value is in array"); } else { alert("Value is not in array"); ids.push(code); } }); }); 

Answer 1

This line:

if($.inArray(code,ids) >= 0)

should be changed to:

if($.inArray(code,ids) != -1)

and put your ids var outside of click.

Try the snippet below.

 var ids = []; jQuery("button").on('click', function() { var sel_fam_rel = jQuery("#my_textbox").val(); code = sel_fam_rel; if ($.inArray(code, ids) != -1) { alert("Value is in array"); } else { alert("Value is not in array"); ids.push(code); } }); 

 <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script> <input type='text' id='my_textbox'> <button>check</button> 

Answer 2

use below code . take your ids out side of click event . as per your code each time when you click button ids reset .

var ids = [];  // declare as global variable
jQuery(document).ready(function()
{
  jQuery("#mybutton").live('click',function () 
  {
    var sel_fam_rel=jQuery("#my_textbox").val();
    code =sel_fam_rel;
    if($.inArray(code,ids) >= 0)
    {
     alert("Value is in array");
    }
   else
   {
     alert("Value is not in array");
     ids.push(code);
    }
 });
});

Answer 3

Create your array var ids=[]; global outside button event, as whenever you click button it is creating new empty array. It will fix your problem.

Answer 4

A few changes are needed:

 var ids = []; // `ids` needs to be in the global scope to work as you want it, // or you could use a different method like localstorage jQuery(document).ready(function() { jQuery("#mybutton").on('click',function () // use `on` not `live` which is deprecated { var sel_fam_rel=jQuery("#my_textbox").val(); code =sel_fam_rel; if($.inArray(code,ids) != -1) // inArray() returns -1 if the value is not in the array, you can use it the way you have it, IMO (purely subjective), using `!=-1` is preferable as it's more clear what the code in intend to do { alert("Value is in array"); } else { alert("Value is not in array"); ids.push(code); } }); }); 

 <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script> <input type="text" id="my_textbox" value="10"/><br> <input type="button" id="mybutton" value="Click me"/> 

Answer 5

I made a fiddle to your problem, Use indexOf

http://jsfiddle.net/go8o34fq/

jQuery-

var array=["A","B","C","D"];

$('button').click(function(){
    var code=$('input').val();
    if(array.indexOf(code)==-1)
    {
        array.push(code);
       console.log("if "+array)
    }
    else
    {
      console.log("else "+array)
    }
});

Just a bit requirement if your need is case-sensitive then use- code.toUpperCase()