Lets say I have javascript objects like this one:
var obj = {
'addr:housenumber': '7',
'addr:street': 'Frauenplan',
'owner': 'Knaut, Kaufmann'
}
How can I check if the object has a property name that starts with addr? I’d imagine something along the lines of the following should be possible:
if (e.data[addr*].length) {
I tried RegExp and .match() to no avail.
You can check it against the Object's keys using Array.some which returns a bool.
if(Object.keys(obj).some(function(k){ return ~k.indexOf("addr") })){
// it has addr property
}
You could also use Array.filter and check it's length. But Array.some is more apt here.
Object.keys(obj.some((k) => ~k.indexOf("addr"));. Waiting for it to come :)
Object.keys() is generated before the call with some(); it's more efficient to check property by property with a for in.You can use the Object.keys function to get an array of keys and then use the filter method to select only keys beginning with "addr".
var propertyNames = Object.keys({
"addr:housenumber": "7",
"addr:street": "Frauenplan",
"owner": "Knaut, Kaufmann"
}).filter(function (propertyName) {
return propertyName.indexOf("addr") === 0;
});
// ==> ["addr:housenumber", "addr:street"];
This gives you existence (propertyNames.length > 0) and the specific names of the keys, but if you just need to test for existence you can just replace filter with some.
Obj = {address: 'ok', x:5}
Object.keys(obj).some(function(prop){
return ~prop.indexOf('add')
}) //true
You can write a function
function check(model) {
var keys = [];
for (key in model) {
if(key.indexOf("addr") > -1)
keys.push(key);
}
return keys;
}
You can check this also with startsWith():
Object.keys(obj).some(i => { return i.startsWith('addr') })
Try this:
var myObject = {
'prop1': 'value1',
'xxxxx': 'value2'
};
var stringToCheck = 'addr';
for(var propertyName in myObject) {
var x = propertyName.substr(0, stringToCheck.length - 1);
if(x == stringToCheck) {
return true;
}
}
I don't think "Querying" a object properties is possible. You would have to loop through the properties individually and determine if they match. something like this...
function findProp(e, prop)
{
for(var o in e.data){
if(o.substr(0, prop.length)==prop) //<- you could try the regex or match operation here
return true;
}
return false;
}
alert(findProp({data:{addr:{street:"a", sub:"b"}}}, 'addr'));
You can then process the property if it findProp returns true...
Why not just
var foo = {'bar':'funtimes'};
if (foo.bar.includes('fun')) {
console.log('match');
}
