Question

我只是用数字更新数据库，但我只希望数字的最后一位数实际更新。我不确定是在PHP还是MySql中执行此操作。

代码:(未发布完整代码，但相关）

if(isset($_POST['update'])) {

$N_Score = $_POST['N_Score'];
$A_Score = $_POST['A_Score'];

$sql = "UPDATE scores SET N_Score = $N_Score, A_Score = $A_Score";
mysql_query($sql) or die(mysql_error());

<form method = "post" action = "<?php $_PHP_SELF ?>">
<table width = "400" border =" 0" cellspacing = "1" cellpadding = "2"> 

<tr>
<td width = "10"><?php echo $N_Team; ?> Score:</td>
<td><input name = "N_Score" type = "text" id = "N_Score" value="<?php echo $N_Score; ?>"></td>
</tr>

<tr>
<td width = "10"><?php echo $A_Team; ?> Score:</td>
<td><input name = "A_Score" type = "text" id = "A_Score" value="<?php echo $A_Score; ?>"></td>
</tr>

因此，在表单中，我输入N_Team和A_Team的分数，如下所示：

N_Team: 21＆amp; A_Team: 34

我只希望最后一个数字真正进入sql字符串的更新，所以在数据库中它看起来像这样：

N_Team: 1＆amp; A_Team: 4

Answer 1

尝试：

$N_Score = substr($_POST['N_Score'], -1);
$A_Score = substr($_POST['A_Score'], -1);

这假定值的长度非零，您可能需要一些错误处理。

您可能还想考虑保护自己免受SQL注入。

Answer 2

这将返回字符串的最后一个字符。

$N_Score = substr($_POST['N_Score'], -1);
$A_Score = substr($_POST['A_Score'], -1);

也许您可以通过转义用户输入来保护系统的完整性：

$N_Score = mysql_real_escape_string(substr($_POST['N_Score'], -1));
$A_Score = mysql_real_escape_string(substr($_POST['A_Score'], -1));

您也可能希望从mysql_*切换到mysqli_*，这已经过改进，可以更好地使用。

请记住，如果字符串的大小为0，则代码将为“位置-1处的无值”或其他内容引发错误。

因此，在添加到数据库之前，最好检查字符串是否包含某些内容。

类似的东西：

if ($_POST['N_Score'] != "" and $_POST['A_Score'] != "")
{
    $N_Score = mysql_real_escape_string(substr($_POST['N_Score'], -1));
    $A_Score = mysql_real_escape_string(substr($_POST['A_Score'], -1));
}

Answer 3

if(isset($_POST['update'])) {

$N_Score = substr($_POST['N_Score'], -1);
$A_Score = substr($_POST['A_Score'], -1);

$sql = "UPDATE scores SET N_Score = $N_Score, A_Score = $A_Score";
mysql_query($sql) or die(mysql_error());

<form method = "post" action = "<?php $_PHP_SELF ?>">
<table width = "400" border =" 0" cellspacing = "1" cellpadding = "2"> 

<tr>
   <td width = "10"><?php echo $N_Team; ?> Score:</td>
   <td><input name = "N_Score" type = "text" id = "N_Score" value="<?php echo $N_Score; ?>"></td>
</tr>

<tr>
   <td width = "10"><?php echo $A_Team; ?> Score:</td>
   <td><input name = "A_Score" type = "text" id = "A_Score" value="<?php echo $A_Score; ?>"></td>
</tr>

更新mysql但只是最后一位数字

3 个答案: