How to check duplication is Stored value in localstorage

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Javascript

LocalStorage

I want to store a localStorage value only once. If it exists in localStorage,an alert appear.

Posted 4-Sep-14 13:21pm

Member 10941024

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kbrandwijk 4-Sep-14 19:30pm

I would add HTML5, and Web Storage tags to make this question easier to find.

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kbrandwijk · Accepted Answer · 2014-09-04T13:29:00

Solution 1

Check if window.localStorage.getItem('...') is null.

Posted 4-Sep-14 13:29pm

kbrandwijk

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Member 10941024 5-Sep-14 17:44pm

this is my code please check with me the value :thank you

$(".aj").click(function(){

var con = localStorage.getItem('noc');//counter for increment key
if(con!=null) {
con = parseInt(con);
} else {
con = -1;
}
con++;
localStorage.setItem('noc',con)

localStorage.setItem('nmdpdt'+parseInt(localStorage.getItem('noc')),$nnpdt);

for(i=0 ; i < localStorage.length ; i++){
key = i;
value = localStorage.getItem('nmdpdt'+i);

if(value === null){
alert("exist");
break;
}else{
alert("not exist");

}

document.write(key+"::::"+value+"</br>");

}

});

kbrandwijk 5-Sep-14 17:49pm

I'm not sure about your question, but shouldn't the check before the alert look like: if (value != null) instead of (value === null)?