How can I do a query to an array javascript, for example I want to find all names that begin with A, an then show all information
Name":"Albert","age":"14"
Name":"Alison","age":"14"
this is my array json:
var house = [{"Name":"Jason","age":"43"},
{"Name":"Albert","age":"14"},
{"Name":"Luck","age":"14"},
{"Name":"Alison","age":"14"},
{"Name":"Tom","age":"12"}]
You can use Array.filter:
var result = house.filter(function(o) {
return o.Name.indexOf("A") === 0;
});
Some old browsers might not support this method. Check the compatibility and the workaround at MDN.
You can use Array.prototype.filter
var names_beginning_a = house.filter(
function (item) {return item["Name"][0].toLowerCase() === 'a';}
);
Once you have this, you could convert your data to a String using JSON.stringify and Array.prototype.map
var dataAsString = names_beginning_a.map(
function (item) {return JSON.stringify(item);} // optionally trim off { and }
);
string[i] access method is not supported in older browsers (IE 6 and 7, for instance). Use string.charAt(i) if you want to be sure.
string[i] they won't support .map or .filter or .stringify either and you'd need to shim all of it.charAt.You can filter an array, to collect the elements with an 'A' name, then forEach or map the matches to a new array of property names and values
house.filter(function(itm){
return itm.Name.charAt(0)== 'A';
}).map(function(o){
var A= [];
for(var p in o){
if(o.hasOwnProperty(p)){
A.push(p+':'+o[p]);
}
}
return A;
}).join('\n');
/* returned value: (String)*/
Name:Albert,age:14
Name:Alison,age:14
If you need a shim:
(function(){
var A= Array.prototype;
if(!A.filter) A.filter= function(fun, scope){
var T= this, A= [], i= 0, itm, L= T.length;
if(typeof fun== 'function'){
while(i<L){
if(i in T){
itm= T[i];
if(fun.call(scope, itm, i, T)) A[A.length]= itm;
}
++i;
}
}
return A;
}
if(!A.map) A.map= function(fun, scope){
var T= this, L= T.length, A= Array(L), i= 0;
if(typeof fun== 'function'){
while(i<L){
if(i in T){
A[i]= fun.call(scope, T[i], i, T);
}
++i;
}
return A;
}
}
}
})();
You could also use grep function
arr = jQuery.grep(house, function (a) { return a.Name.indexOf("A") === 0; });
