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@pjschreifels
Last active December 14, 2015 13:38
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#javascript #ORM manipulates a browser's Local Storage with create, update, increment, decrement and delete. Also provides functions for getting data with get, get all, find value, and find. The script treats the Local Storage like a database (as much as possible), so when manipulating the data, the function requires: table - a string that refer…
function createStore(table, row){ // Inserts a single row of data into a table
var rows = JSON.parse(localStorage.getItem(table));
if (rows == null) {
rows = {};
var id = 1;
} else {
var id = $.map(Object.keys(rows), function(val, i){return parseInt(val);}).reduce(function(a,b){return Math.max(a,b);})+1;
}
row.id = id;
rows[id.toString()] = row;
storeLocal(table, rows);
return id;
}
function updateStore(table, row, id){ // Updates a single row of a table by id
var rows = JSON.parse(localStorage.getItem(table));
rows[id] = row;
storeLocal(table, rows);
}
function incrementValueStore(table, id, column, amount){
var update = getStore(table, id);
var count = parseInt(update[table][0][column])+parseInt(amount);
update[table][0][column] = count;
row = update[table][0];
updateStore(table, row, id);
}
function decrementValueStore(table, id, column, amount){
var update = getStore(table, id);
var count = parseInt(update[table][0][column])-parseInt(amount);
update[table][0][column] = count;
row = update[table][0];
updateStore(table, row, id);
}
function deleteStore(table, id){ // Deletes a single row of a table by id
var rows = JSON.parse(localStorage.getItem(table));
delete rows[id];
storeLocal(table, rows);
}
function getAllStore(table) { // Returns all rows from a table
var rows = JSON.parse(localStorage.getItem(table));
var data = [];
if (rows != null) {
for(id in rows){
data.push(rows[id]);
}
var result = {};
result[table] = data;
return result;
}
return null;
}
function getStore(table, id){ // Returns a single row from a table by matching id
var rows = JSON.parse(localStorage.getItem(table));
if (rows != null){
var data = [];
data.push(rows[id]);
var result = {};
result[table] = data;
return result;
} else {
return null;
}
}
function findStore(table, find){ // Find is an array of columns and values to return matching rows of a table. i.e. SHOW * WHERE column = value AND column = value, etc.
var rows = JSON.parse(localStorage.getItem(table));
var data = [];
var i = 0;
$.map(find, function(){ i++; });
for (var id in rows) {
var row = rows[id];
var n = 0;
$.map(find, function(c,v){
var mapthis = v + ":" + c;
$.map(row, function(c,v){
var tothis = v + ":" + c;
if(mapthis == tothis){
n++;
}
})
});
if ( i == n ){data.push(rows[id]);}
}
if (data.length == 0) {
return null;
} else {
var result = {};
result[table] = data;
return result;
}
}
// This one needs an ID
function findValueStore(table, column){ // Returns the value of a column in a specified row of a table
var rows = JSON.parse(localStorage.getItem(table));
var data = [];
for (var id in rows) {
var row = rows[id];
for (var find in row) {
if (find == column){ return row[find]; }
}
}
}
function storeLocal(table, rows) {
try {
localStorage.setItem( table, JSON.stringify(rows) );
} catch (error) {
if (error == QUOTA_EXCEEDED_ERR) {
alert('Quota exceeded!');
}
}
location.reload();
}
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