1.使用內(nèi)置對(duì)象創(chuàng)建數(shù)據(jù)庫

 $mysqli = mysqli_init();
    if (!$mysqli) {
        die('mysqli_init failed');
    }

2.連接數(shù)據(jù)庫

if (!$mysqli->real_connect('localhost', 'root', '', 'test')) {
        die('Connect Error (' . mysqli_connect_errno() . ') '
                . mysqli_connect_error());
 }

3.設(shè)置字符集

if (!$mysqli->set_charset("utf8")) {
    printf("Error loading character set utf8: %s\n", $mysqli->error);
    } else {
        printf("Current character set: %s\n", $mysqli->character_set_name());
    }

4.sql語句使用（增薯鼠，刪郎任，改，查）

    //創(chuàng)建
    $q = "CREATE TABLE Persons 
        (
        FirstName varchar(15),
        LastName varchar(15),
        Age int
        )";

    //插入
    //$q = "INSERT INTO name1 (name, age) VALUES ('黃鵬','4')";
    //查詢數(shù)據(jù)
   // $q = "SELECT * FROM user";
    // 更新
    //$q="UPDATE user SET name = '還耕' WHERE age = '13'";
    //刪除
    $q="DELETE FROM user WHERE age='4'";

注意： 在寫數(shù)據(jù)庫語句是枉长，防止引號(hào)和其他有問題的字符破壞SQL命令的語法。我們需要

//將變量進(jìn)行轉(zhuǎn)義琼讽；
$var = $mysqli->real_escape_string($var);

5.查詢

$result = $mysqli->query($q);

6.返回結(jié)果集

if ($result = $mysqli->query($q)) {
     while ($row = $result->fetch_row()) {
                 printf("%s\n", $row[1]);
             }

         /* free result set 關(guān)閉結(jié)果集*/
         $result->close();
    }

//如果想直接返回json
$i=0必峰；
if ($result = $mysqli->query($sql)) {
            while ($row = $result->fetch_object()) {
                  
                     $param[$i++]=$row;
                 }
                echo json_encode($param);
             /* free result set 關(guān)閉結(jié)果集*/
             $result->close();

        }

7.關(guān)閉數(shù)據(jù)庫

$mysqli->close();

8.前臺(tái)發(fā)到后臺(tái)數(shù)據(jù)也是json的方法##

$.ajax({
                    url:url,
                   data:JSON.stringify(data),
                   type:'post',
                   dataType:'json',
                   headers:{
                    Accept:"application/json",
                    "Content-Type":"application/json"
                   }
                  })
                  .done(function() {
                    console.log("success");
                  })
                  .fail(function() {
                    console.log("error");
                  })
                  .always(function() {
                    console.log("complete");
                  });