Membangun sebuah situs web dari awal Bagian IX:. Mengambil data dengan SQL.
Apa yang akan kita lakukan
Dalam bab ini kita akan:
- Buat halaman server
Server Menjalankan PHP dan MySQL
<?php
header("Access-Control-Allow-Origin: *");
header("Content-Type:
application/json; charset=UTF-8");
$conn =
new mysqli("myServer", "myUser", "myPassword", "Northwind");
$result = $conn->query("SELECT
CompanyName, City, Country FROM Customers");
$outp = "";
while($rs = $result->fetch_array(MYSQLI_ASSOC)) {
if ($outp != "") {$outp .= ",";}
$outp .= '{"Name":"' . $rs["CompanyName"] . '",';
$outp .= '"City":"' . $rs["City"] . '",';
$outp .= '"Country":"'. $rs["Country"] . '"}';
}
$outp ='{"records":['.$outp.']}';
$conn->close();
echo($outp);
?>
Permintaan HTTP Cross-Site
Permintaan data dari server yang berbeda (dari halaman yang meminta), disebut permintaan HTTP cross-site.
permintaan cross-site sangat umum di web. Banyak halaman memuat css, gambar, atau script dari server yang berbeda.
Di browser modern, permintaan HTTP lintas situs dari script dibatasi ke situs yang sama untuk alasan keamanan.
Baris berikut, dalam contoh PHP di atas, telah ditambahkan untuk memungkinkan akses ke halaman dari sebuah cross-site.
header("Access-Control-Allow-Origin: *");
Server Menjalankan PHP dan MS Access
<?php
header("Access-Control-Allow-Origin: *");
header("Content-Type:
application/json; charset=ISO-8859-1");
$conn = new COM("ADODB.Connection");
$conn->open("PROVIDER=Microsoft.Jet.OLEDB.4.0;Data Source=Northwind.mdb");
$rs = $conn->execute("SELECT CompanyName, City, Country FROM
Customers");
$outp = "";
while (!$rs->EOF) {
if ($outp != "") {$outp .= ",";}
$outp .= '{"Name":"' . $rs["CompanyName"] . '",';
$outp .= '"City":"' . $rs["City"] . '",';
$outp .= '"Country":"'. $rs["Country"] . '"}';
$rs->MoveNext();
}
$outp ='{"records":['.$outp.']}';
$conn->close();
echo ($outp);
?>
Server Menjalankan ASP.NET, VB dan MS Access
<%@ Import Namespace="System.IO"%>
<%@ Import Namespace="System.Data"%>
<%@ Import Namespace="System.Data.OleDb"%>
<%
Response.AppendHeader("Access-Control-Allow-Origin", "*")
Response.AppendHeader("Content-type",
"application/json")
Dim conn As
OleDbConnection
Dim objAdapter As OleDbDataAdapter
Dim objTable As
DataTable
Dim objRow As DataRow
Dim objDataSet As New DataSet()
Dim outp
Dim c
conn = New OledbConnection("Provider=Microsoft.Jet.OLEDB.4.0;data
source=Northwind.mdb")
objAdapter = New OledbDataAdapter("SELECT
CompanyName, City, Country FROM Customers", conn)
objAdapter.Fill(objDataSet,
"myTable")
objTable=objDataSet.Tables("myTable")
outp = ""
c = chr(34)
for each x in objTable.Rows
if outp <> "" then outp = outp & ","
outp = outp & "{" & c & "Name" & c & ":" & c & x("CompanyName")
& c & ","
outp = outp & c & "City" & c & ":" & c
& x("City") & c & ","
outp = outp & c & "Country" & c
& ":" & c & x("Country") & c & "}"
next
outp
="{" & c & "records" & c & ":[" & outp & "]}"
conn.close
response.write(outp)
%>
Server Menjalankan ASP.NET, Razor dan SQL Lite
@{
Response.AppendHeader("Access-Control-Allow-Origin", "*")
Response.AppendHeader("Content-type",
"application/json")
var db =
Database.Open("Northwind");
var query = db.Query("SELECT CompanyName,
City, Country FROM Customers");
var outp =""
var
c = chr(34)
}
@foreach(var row in
query)
{
if outp <> "" then outp = outp + ","
outp = outp + "{" + c + "Name" + c + ":" + c
+ @row.CompanyName + c + ","
outp = outp + c
+ "City" + c + ":" + c
+ @row.City + c + ","
outp = outp
+ c + "Country" + c
+ ":" + c + @row.Country + c + "}"
}
outp ="{" + c
+ "records" + c + ":[" + outp + "]}"
@outp