75 lines
1.6 KiB
HTML
75 lines
1.6 KiB
HTML
<!DOCTYPE html>
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<html lang="en">
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<head>
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<meta charset="UTF-8">
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<meta http-equiv="X-UA-Compatible" content="IE=edge">
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<meta name="viewport" content="width=device-width, initial-scale=1.0">
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<title>留言</title>
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<style>
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* {
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margin: 0;
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padding: 0;
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border: none;
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outline: none;
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}
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.main {
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width: 400px;
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height: 300px;
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border: 1px solid #000;
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position: relative;
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}
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.main textarea {
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width: 100%;
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height: 100%;
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resize: none;
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}
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.main .tips {
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position: absolute;
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right: 10px;
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bottom: 10px;
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}
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.hui {
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color: #cfc8c8;
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}
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.red {
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color: red;
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}
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</style>
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</head>
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<body>
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<div class="main">
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<textarea name="" id=""></textarea>
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<span class="tips hui">100/100</span>
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</div>
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</body>
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<script>
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var message = document.querySelector("textarea"),
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tips = document.querySelector(".main .tips"),
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total = 100;
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message.oninput = function () {
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var sy = total - message.value.length;
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if (sy <= 0) {
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// 超过限制
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tips.innerText = "已达限制"
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// replace 替换，将 hui 替换 成 red
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tips.classList.replace("hui", "red")
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message.value = message.value.substring(0, 100)
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} else {
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tips.innerText = `100/${sy}`
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tips.classList.replace("red", "hui")
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}
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}
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</script>
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</html> |