JavaScript 代码示例：验证表单并控制按钮状态

// This code adds a click event listener to a button with an id of 'block'+block+'chain'+chain+'validateButton' // When the button is clicked, it prevents the default form submit behavior // It then creates a Ladda loading spinner on the button // After a delay of 250 milliseconds, it checks the validity of the form inputs // If the inputs are valid, it enables a button with an id of 'block'+block+'chain'+chain+'mineButton' // If the inputs are not valid, it changes the background color of a card element with an id of 'block'+block+'chain'+chain+'card' to orange // It also disables the 'block'+block+'chain'+chain+'mineButton' button // Finally, it stops the Ladda loading spinner $('#block' + block + 'chain' + chain + 'validateButton').click(function(e) { e.preventDefault(); var l = Ladda.create(this); l.start(); setTimeout(function() { var valid = true; for (var ty = 0; ty < txCount; ty++) { var value = parseInt($('#block' + block + 'chain' + chain + 'tx' + ty + 'value').val()); var from = $('#block' + block + 'chain' + chain + 'tx' + ty + 'from').val(); var to = $('#block' + block + 'chain' + chain + 'tx' + ty + 'to').val(); if (blcs.hasOwnProperty(account)) { var blc = blcs[account]; } else { var blc = 0; } if (value > blc) { valid = false; } } if (valid) { $('#block' + block + 'chain' + chain + 'mineButton').attr('disabled', false); // 挖矿按钮可用 } else { $('#block' + block + 'chain' + chain + 'card').css('background-color', 'orange'); $('#block' + block + 'chain' + chain + 'mineButton').attr('disabled', true); } l.stop(); }, 250); // give UI time to update });