Question

我们可以使用以下函数提醒消息吗？

var run_databases = function() {
    alert('welcome');
};

window.setTimeout(run_databases, 1000);

Answer 1

不需要其他功能包装（闭包）：

＆＃13;

var run_databases = function() {
  alert('welcome');
};

window.setTimeout(run_databases, 1000);

＆＃13;

Answer 2

您需要命名该函数或将其分配给变量：

＆＃13;

var run_databases = function() {
  alert('welcome');
};

// You need to name this function
function setTimeOutFoo() {

  window.setTimeout(run_databases, 1000);

};

// Or assign the unnamed function to a variable
var setTimeOutVar = function() {

  window.setTimeout(run_databases, 1000);

};

setTimeOutFoo(); // Calling the function
setTimeOutVar();

＆＃13;

您可以尝试这样的事情：

＆＃13;

window.onload = function() {
  console.log('Page has finished loading');  
  
  //I am adding a time out so you can see the loading
  // You can remove the "setTimeout(function () {"
  // And you can also remove the "}, 2000);"
  
  setTimeout(function () { // Remove this line
    
    document.getElementById('loading').innerHTML = "Page Loaded";
    
  }, 2000); // Remove this line
  
};

＆＃13;

<p id="loading">Page Loading...</p>

＆＃13;

向按钮添加工具提示的最简单方法是：

＆＃13;

var btn = document.getElementById("btn");

btn.setAttribute('title', 'This is the tool tip set in JavaScript');

＆＃13;

<!-- Done with JavaScript -->
<button id="btn">Hover here!</button> 

<!-- Done in the HTML -->
<button id="btn" title="This is tool tip set in HTML">No! Hover here :)</button>

＆＃13;

Answer 3

您正在使用自调用匿名函数，但语法错误：

var run_databases = function() {
  alert('welcome');
};

(function(){
   window.setTimeout(run_databases, 1000);
})();

Working example

我们可以使用以下代码执行警报消息吗？

3 个答案: