php中是否有办法自动从数据库中获取值？
基本上，如果我有一个选择框＆amp;我选择选项“Laptop-01”，PHP中有没有办法检查该行的数据库，然后自动获取Laptop-01的序列号，并在文本框中填入设备序列号。
目前我只有两个文本框，用户需要手动输入产品编号（Laptop-01）和＆amp;然后是序列号。
我目前有以下代码;
PHP
<?php
$selectquery = "SELECT * FROM `loanproducts`";
$selectresult = mysqli_query($connection, $selectquery);
$selectusersquery = "SELECT * FROM `loanusers`";
$selectusersresult = mysqli_query($connection, $selectusersquery);
if (isset($_POST['editloan'])):
$loanid = $_POST["loanid"];
$username = $_POST["username"];
$product=$_POST["product"];
$product_desc=$_POST["product_desc"];
$serial=$_POST["serial"];
$date_collected=$_POST["date_collected"];
$date_return = $_POST["date_return"];
$returned = $_POST["returned"];
$edit_query="UPDATE loans SET
username = '$username',
product = '$product',
product_desc = '$product_desc',
serial = '$serial',
date_collected ='$date_collected',
date_return = '$date_return',
returned = '$returned'
WHERE loanid ='$loanid'";
$edit_result= mysqli_query($connection, $edit_query);
if ($edit_result) :
header ('location: editloan.php?confirm=Loan successfully updated');
else :
echo "<b>This didn`t work, error: </b>";
echo mysqli_error($connection);
endif;
endif;
$loanid=$_GET['loanid'];
$my_query="select * from loans where loanid=$loanid";
$result= mysqli_query($connection, $my_query);
while ($myrow = mysqli_fetch_array($result)):
$username = $myrow["username"];
$product = $myrow["product"];
$product_desc = $myrow["product_desc"];
$serial = $myrow["serial"];
$date_collected=$myrow["date_collected"];
$date_return=$myrow["date_return"];
$returned=$myrow["returned"];
endwhile;
?>
HTML
<html>
<h2 align="center">Edit Product Form</h2>
<body>
<div id="loginp"<p align="center">Edit this loan for the Coleg Sir Gar Loan System</p></div>
<form method="POST" action="editloaninfo.php">
<div id="editp"><p align="center">
<label class="labelform">Username:</label><select name="username" style="width: 150px">
<?php while($row1 = mysqli_fetch_array($selectusersresult))
{ if ( $row1[1] == $username )
$selected = "selected";
else $selected = "";
echo "<option $selected>{$row1[1]}</option>";
}?>
</select></p></div>
<div id="editp"><p align="center">
<label class="labelform">Product:</label><select name="product" style="width: 150px">
<?php while($row1 = mysqli_fetch_array($selectresult))
{ if ( $row1[1] == $product )
$selected = "selected";
else $selected = "";
echo "<option $selected>{$row1[1]}</option>";
}?>
</select></p></div>
<div id="editp"><p align="center">
<label class="labelform">Product Description:</label><input class="inputform" type="text" name="product_desc" placeholder="Product Description..." autocomplete="off" required size="18" value="<?php echo $product_desc; ?>"></p></div>
<div id="editp"><p align="center">
<label class="labelform">Serial Number:</label><input class="inputform" type="text" name="serial" placeholder="Serial Number..." autocomplete="off" required size="18" value="<?php echo $serial; ?>"></p></div>
<div id="editp"><p align="center">
<label class="labelform">Date Collected:</label><input class="inputform" type="date" name="date_collected" autocomplete="off" size="30" value="<?php echo $date_collected; ?>"></p></div>
<div id="editp"><p align="center">
<label class="labelform">Date Returned:</label><input class="inputform" type="date" name="date_return" autocomplete="off" size="30" value="<?php echo $date_return; ?>"></p></div>
<div id="editp"><p align="center">
<label class="labelform">Returned:</label><select name="returned" style="width: 150px">
<option value="Yes" <?php echo $returned === 'Yes' ? 'selected="selected"' : '' ?>>Yes</option>
<option value="No" <?php echo $returned === 'No' ? 'selected="selected"' : '' ?>>No</option>
</select></p></div>
<br>
<input type="hidden" name=loanid value= "<?php echo $loanid; ?>" >
<div id="editp"><input class="inputform" type="submit" name="editloan" value="Save Changes">
<input class="inputform" type="button" name="Cancel" value="Cancel" onClick="window.location.href='editloan.php'"></div>
</form>
</body>
</html>
</div>
答案 0 :(得分：0)
基本上你想做的是：
当用户选择“Laptop-01”时，您必须使用与用户笔记本电脑相关的信息（如序列号）更新所有INPUTS。这可以通过添加AJAX
请注意：此答案将为您提供有关如何从数据库填充数据的信息，然后您可以针对您需要的任何信息执行此操作。
library("shiny")
library("highcharter")
data(citytemp)
ui <- fluidPage(
h1("Highcharter EXAMPLE"),
fluidRow(
column(width = 8,
highchartOutput("hcontainer",height = "500px")
),
selectInput("option", label = "", width = "100%",
choices = c("Tokyo", "NY"))
)
)
server <- function(input, output) {
data <- citytemp[,c("month","tokyo","new_york")]
data = data[data$month%in%c("Dec","Jan","Feb","Mar"),]
choose_Option <- reactive({
sort_option <- input$option
if(sort_option=="Tokyo"){
data = data[order(data$tokyo),]
}
else{
data = data[order(data$new_york),]
}
return(data)
})
output$hcontainer <- renderHighchart({
data = choose_Option()
data = data[1:3,]
chart <- highchart() %>%
hc_chart(type = "bar") %>%
hc_title(text = "Monthly Average Temperature for main cities") %>%
hc_subtitle(text = "Source: WorldClimate.com") %>%
hc_xAxis(categories = data$month ,
labels=list(
formatter=JS("function () {
return 'Tokyo' + '<br>' + this.categories +' ' + '<br>'+'NY' + '</br>';
}"))) %>%
hc_yAxis(title = list(text = "Temperature (C)"))
hc <- chart %>% hc_add_series(yAxis=0,name="Tokyo",data = data$tokyo,colorByPoint=TRUE )
hc <- hc %>% hc_add_series(yAxis=0,name="NY",data = data$new_york,colorByPoint=TRUE )
return(hc)
})
}
shinyApp(ui = ui, server = server)
Ajax.js
<form>
<select id='product_name' onchange="get_data()">
<option value='Laptop-01'>Laptop-01</option>
</select>
<input name='serial_no' id='serial_no'>
<input name='product_no' id='product_no'>
</form>
<script src="js/ajax.js"></script>
<script>
function get_data(){
//In very short what this do is :
//get values
var serial_no = document.getElementById('product_name').value;
//create an Object
var ajax = ajaxObj("POST", "yourpage.php");
ajax.onreadystatechange = function() {
if(ajaxReturn(ajax) == true) {
//ajax.responsetex is things you echo from script next to it
var index1 = ajax.responseText.split(",");
//index1 is array holding values
//index1[0]=$serial_no
//index1[1]=$product_no
//Now set value of your serian_no INPUT to $serial_no = index1[0];
document.getElementById('serial_no').value = index1[0];
document.getElementById('product_no').value = index1[1]
}
}
//ajax.send = POST/GET method
ajax.send("product_name="+product_name);
}
</script>
<?php
if(isset($_POST['product_name'])){
$sql = "SELECT serial_no,product_no FROM loanuser WHERE username='$username'";
$query = ($connection , $query);
while ($myrow = mysqli_fetch_array($query)){
$serial_no = $myrow["serial_no"];
$product_no = $myrow["product_no"];
}
//form a (,) separated list and echo it.
echo $serial_no.",".$product_no;
exit();
}
?>
如果您希望我在此页面中添加更多关于AJAX的说明，请在评论部分添加请求我会将其编辑为更好的答案