var slider = document.getElementById("brightnessSlider"); var output = document.getElementById("brightnessValue"); output.innerHTML = slider.value; slider.oninput = function() { output.innerHTML = this.value; sendBrightness(this.value); }这几句话是什么意思
时间: 2024-03-19 09:40:17 浏览: 145
这是一段 JavaScript 代码,它用于创建一个名为"brightnessSlider"的 HTML 元素,并将其与另一个名为"brightnessValue"的元素关联。当用户改变"brightnessSlider"的值时,会调用名为"sendBrightness"的函数,并将其新值传递给该函数。同时,该值也会更新显示在"brightnessValue"元素上。这段代码的功能是让用户调整亮度值,并在用户调整亮度时将其发送到其他地方进行处理。
相关问题
<!DOCTYPE html><html><head> <meta charset="UTF-8"> <title>ESP8266 LED Control</title> <style> </style></head><body> <h1>ESP8266 LED Control</h1> <input type="range" min="0" max="255" value="0" id="brightnessSlider" oninput="onput_function();"> <p id="brightnessValue">Brightness: 0</p> <script> function onput_function() { var slider = document.getElementById("brightnessSlider"); var output = document.getElementById("brightnessValue"); output.innerHTML = "值为" + slider.value; } function sendBrightness(value) { var xhttp = new XMLHttpRequest(); xhttp.onreadystatechange = function() { if (this.readyState == 4 && this.status == 200) { console.log("Brightness set to: " + value); } }; xhttp.open("GET", "/brightness?value=" + value, true); xhttp.send(); } </script></body></html>和<!DOCTYPE html><html><head> <meta charset="UTF-8"> <title>ESP8266 LED Control</title> <style> </style></head><body> <h1>ESP8266 LED Control</h1> <input type="range" min="0" max="255" value="0" id="brightnessSlider" oninput="onput_function();"> <p id="brightnessValue">Brightness: 0</p> <script> function onput_function() {var slider = document.getElementById("brightnessSlider"); var output = document.getElementById("brightnessValue"); output.innerHTML = "值为" + this.value; }); function sendBrightness(value) { var xhttp = new XMLHttpRequest(); xhttp.onreadystatechange = function() { if (this.readyState == 4 && this.status == 200) { console.log("Brightness set to: " + value); } }; xhttp.open("GET", "/brightness?value=" + value, true); xhttp.send(); } </script>body></html>是完全一样的吗
不完全一样,第二个 HTML 代码存在语法错误。在第二个代码中,`onput_function()` 函数的语法是不正确的,应该是 `oninput_function()`。此外,`onput_function()` 函数的代码也被修改了,导致其与第一个代码不同。在第二个代码中,`onput_function()` 函数的代码是:
```
function onput_function() {
var slider = document.getElementById("brightnessSlider");
var output = document.getElementById("brightnessValue");
output.innerHTML = "值为" + this.value;
});
```
这段代码多了一个右括号 `)`,而且没有与前面的左括号 `(` 匹配。正确的代码应该是:
```
function oninput_function() {
var slider = document.getElementById("brightnessSlider");
var output = document.getElementById("brightnessValue");
output.innerHTML = "Brightness: " + slider.value;
}
```
除此之外,两个 HTML 代码是完全一样的。
<!DOCTYPE html><html><head> <meta charset="UTF-8"> <title>ESP8266 LED Control</title> <style> </style></head><body> <h1>ESP8266 LED Control</h1> <input type="range" min="0" max="255" value="0" id="brightnessSlider" oninput="onput_function();"> <p id="brightnessValue">Brightness: 0</p> <script> function onput_function() {var slider = document.getElementById("brightnessSlider"); var output = document.getElementById("brightnessValue"); output.innerHTML = "值为" + this.value; }); function sendBrightness(value) { var xhttp = new XMLHttpRequest(); xhttp.onreadystatechange = function() { if (this.readyState == 4 && this.status == 200) { console.log("Brightness set to: " + value); } }; xhttp.open("GET", "/brightness?value=" + value, true); xhttp.send(); } </script>body></html>把这段代码整理成网页格式
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>ESP8266 LED Control</title>
<style>
</style>
</>
<body>
<h1>ESP8266 LED Control</h1>
<input type="range" min="0" max="255" value="0" id="brightnessSlider" oninput="onput_function();">
<p id="brightnessValue">Brightness: 0</p>
<script>
function onput_function() {
var slider = document.getElementById("brightnessSlider");
var output = document.getElementById("brightnessValue");
output.innerHTML = "值为" + this.value;
});
function sendBrightness(value) {
var xhttp = new XMLHttpRequest();
xhttp.onreadystatechange = function() {
if (this.readyState == 4 && this.status == 200) {
console.log("Brightness set to: " + value);
}
};
xhttp.open("GET", "/brightness?value=" + value, true);
xhttp.send();
}
</script>
</body>
</html>
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