js获取表单input的值

<input type="text" id="myInput">
<button onclick="getValue()">获取值</button>

<script>
function getValue() {
    var inputValue = document.getElementById('myInput').value;
    console.log(inputValue);
}
</script>

<input type="text" class="myInput">
<button onclick="getValue()">获取值</button>

<script>
function getValue() {
    var inputValue = document.querySelector('.myInput').value;
    console.log(inputValue);
}
</script>

<form id="myForm">
    <input type="text" name="myInput">
    <button type="button" onclick="getValue()">获取值</button>
</form>

<script>
function getValue() {
    var inputValue = document.getElementById('myForm').elements['myInput'].value;
    console.log(inputValue);
}
</script>

window.onload = function() {
    // 你的代码
};