JavaScript 中的函数数组

给定一个包含函数的数组，任务是使用 JavaScript 以不同的方式访问其元素。

方法：

• 声明一个函数数组。
• 函数数组与数组函数等索引一起使用。

示例 1：在此示例中，函数调用是从数组元素开始的，但函数是在其他地方定义的。我们可以在调用时将参数传递给函数。

 
 
     
         
            Array of functions in javascript
        
     
      
     
          
         
            GeeksForGeeks 
        
          
        
        
          
        
            click here
        
          
        
        
          
        
            var up = document.getElementById('GFG_UP');
            var down = document.getElementById('GFG_DOWN');
              
            function firstFun(str) {
                down.innerHTML = str;
            }
            function secondFun(str) {
                down.innerHTML = str;
            }
            function thirdFun(str) {
                down.innerHTML = str;
            }
              
            // Declare array of functions
            var arrayOfFunction = [
                firstFun,
                secondFun,
                thirdFun     
            ]
              
            up.innerHTML = "Calling function from the array of functions";
              
            // Function call
            function GFG_Fun() {
                arrayOfFunction[0]("This is first function");
            }
         
     
                    

输出：

• 在点击按钮之前：
  
• 点击按钮后：
  

示例 2：在此示例中，函数（匿名）本身被定义为数组的元素。我们可以通过访问数组元素后跟 () 来访问它。

 
 
     
         
            Array of functions in JavaScript
        
     
      
     
          
         
            GeeksForGeeks 
        
          
        
        
          
        
            click here
        
          
        
        
          
        
            var up = document.getElementById('GFG_UP');
            var down = document.getElementById('GFG_DOWN');
              
            // Declare an array of functions
            var arrayOfFunction = [
                function() {
                    down.innerHTML = "Inside First function";
                },
                  
                function() {
                    down.innerHTML = "Inside Second function";
                },
                  
                function() {
                    down.innerHTML = "Inside Third function";
                }     
            ]
              
            up.innerHTML = "Calling function from the array of functions";
              
            function GFG_Fun() {
                arrayOfFunction[2]();
            }
         
     
                    

输出：

• 在点击按钮之前：
  
• 点击按钮后：