我想将一个JSON字符串发送到一个包含一些用户信息的PHP文件，然后将该信息插入MySQL数据库。
我的HTML:
<!DOCTYPE html>
<head>
<script src="script.js"></script>
</head>
<body>
<form name="form1" action="" onSubmit="sub()">
<input type="text" name="username" id="usrnm" />
<input type="text" name="password" id="pswrd" />
<input type="text" name="firstname" id="frstnm" />
<input type="text" name="surname" id="surnm" />
<input type="submit" value="Submit" />
</form>
</body>
</html>
script.js:中的我的Javascript
function sub() {
var un = document.getElementById("usrnm").value;
var pw = document.getElementById("pswrd").value;
var fn = document.getElementById("frstnm").value;
var sn = document.getElementById("surnm").value;
var jsonObj = {username:un, password:pw, firstName:fn, surName:sn};
var xmlhttp = new XMLHttpRequest();
xmlhttp.open("POST","server.php" ,true);
xmlhttp.setRequestHeader("Content-type","application/x-www-form-urlencoded");
xmlhttp.send("data="+encodeURIComponent(JSON.stringify(jsonObj)));
};
我的PHP:
<?php
$con=mysqli_connect("localhost","root","", "somedatabase");
$data = $_POST["data"];
$res = json_decode($data, true);
mysqli_query($con,"INSERT INTO sometable (username,password,firstname,surname) VALUES ($res[username],$res[password],$res[firstname],$res[surname])");
mysqli_close($con);
?>
当我用普通字符串值替换insert语句中的值时，我的PHP会在DB中插入一个新行，但当我尝试使用PHP对象中的值的时候，不会插入任何内容。
让它像一样
VALUES (" . $res['username'] . "," . $res['password'] . "," . $res['firstname'] . "," . $res['surname']. ")"
而不是直接在字符串中。PHP不会接受这一点。
使用文本作为键的数组应该始终被引用。例如$array_name['key']
因此，请尝试将查询行更改为
mysqli_query($con,"INSERT INTO sometable (username,password,firstname,surname) VALUES ($res['username'],$res['password'],$res['firstname'],$res['surname'])");
如果您仍然有问题，请尝试测试$res 的结果
print_r($res);