Scala Map transform() 方法与示例

transform()方法用于将地图的元素转换为可变地图。

Method Definition: def transform(f: (K, V) => V): Map.this.type

Return Type: It transforms all the elements of the map and returns them into a mutable map.

示例 #1：

// Scala program of transform()
// method
  
// Creating object
object GfG
{ 
  
    // Main method
    def main(args:Array[String])
    {
      
        // Creating a map
        val m1 = Map(3 -> "geeks", 4 -> "for", 2 -> "cs")
          
        // Applying transform method
        val result = m1.transform((key,value) => value.toUpperCase)
          
        // Displays output
        println(result)
      
    }
}

输出：

Map(3 -> GEEKS, 4 -> FOR, 2 -> CS)

示例 #2：

// Scala program of transform()
// method
  
// Creating object
object GfG
{ 
  
    // Main method
    def main(args:Array[String])
    {
      
        // Creating a map
        val m1 = Map(3 -> "geeks", 4 -> "for", 4 -> "for")
          
        // Applying transform method
        val result = m1.transform((key,value) => value.toUpperCase)
          
        // Displays output
        println(result)
      
    }
}

输出：

Map(3 -> GEEKS, 4 -> FOR)