如何将 JavaScript 函数存储在队列中并按该顺序执行？

任务是在 JavaScript 的帮助下按照队列中定义的顺序执行函数。下面讨论两种方法。

方法一：声明函数并使用数组push()方法将函数推送到数组中。后面遍历数组，一一执行函数。

• 示例：此示例实现了上述方法。

      
          
              Store JavaScript functions in 
              a queue and execute in that order
          
      
      
          
              GeeksforGeeks
          
          
          
              Click Here
          
          
          
              var up = document.getElementById("GFG_UP");
              up.innerHTML = 
                "Click on the button to execute "+
                "the function in order of queue";
              var down = document.getElementById("GFG_DOWN");
              function myGFG() {
                  
                  // First function
                  function function1() {
                      alert("First Function");
                  }
                  
                  // Second function
                  function function2() {
                      alert("Second Function");
                  }
                  var orderQueue = [];
                  
                  // Push them in queue
                  orderQueue.push(function1);
                  orderQueue.push(function2);
                  while (orderQueue.length > 0) {
                      // Execute in order
                      orderQueue.shift()();
                  }
                  down.innerHTML = 
                    "Functions executed in queue order";
              }
          
      

• 输出：

方法2：声明函数并使用数组索引将函数按顺序分配给数组的索引。后面遍历数组，一一执行函数。

• 示例：此示例实现了上述方法。

      
          
              Store JavaScript functions in a 
              queue and execute in that order
          
      
      
          
              GeeksforGeeks
          
          
          
              Click Here
          
          
          
              var up = document.getElementById("GFG_UP");
              up.innerHTML = 
                "Click on the button to execute "+
                "the function in order of queue";
              var down = document.getElementById("GFG_DOWN");
              function myGFG() {
                  
                  // First function
                  function function1() {
                      alert("First Function");
                  }
                  
                  // Second function
                  function function2() {
                      alert("Second Function");
                  }
                  var functions = new Array();
                  // Adding the functions in the order
                  // in queue(array)
                  functions[0] = function1;
                  functions[1] = function2;
                  for (var i = 0; i < functions.length; i++) {
                      
                      // Executing them in order.
                      functions[i].call();
                  }
                  down.innerHTML = 
                      "Functions executed in queue order";
              }
          
      

• 输出：