c - 简化多个 elseif 语句

Question

我目前正在开发一个项目，该项目使用键盘数字作为传感器 (f_temp) 的保存位置并将其保存到 float 组 sensorData[] 中，u8_key 是识别按键的变量。我如何在不使用多个 else if 语句的情况下改进这一点？

void saveValue(void){
      if (u8_key == '1'){
            writeLCD(0x01,0,0,1); // clears LCD
            sensorData[0] = f_temp;
            outStringLCD("Saved to 1"); // writes to LCD for visual confirmation of value being saved and to what location on LCD
          }

         else if (u8_key == '2'){
            writeLCD(0x01,0,0,1);
            sensorData[1] = f_temp;
            outStringLCD("Saved to 2");
         }

        else if (u8_key == '3'){
            writeLCD(0x01,0,0,1);
            sensorData[2] = f_temp;
            outStringLCD("Saved to 3");
      }         
              else if (u8_key == '4'){
            writeLCD(0x01,0,0,1);
            sensorData[3] = f_temp;
            outStringLCD("Saved to 4");
      } 
        else if (u8_key == '5'){
            writeLCD(0x01,0,0,1);
            sensorData[4] = f_temp;
            outStringLCD("Saved to 5");
      } 
        else if (u8_key == '6'){
            writeLCD(0x01,0,0,1);
            sensorData[5] = f_temp;
            outStringLCD("Saved to 6");
      } 
        else if (u8_key == '7'){
            writeLCD(0x01,0,0,1);
            sensorData[6] = f_temp;
            outStringLCD("Saved to 7");

      } 
        else if (u8_key == '8'){
            writeLCD(0x01,0,0,1);
            sensorData[7] = f_temp;
            outStringLCD("Saved to 8");

      } 
        else if (u8_key == '9'){
            writeLCD(0x01,0,0,1);
            sensorData[8] = f_temp;
            outStringLCD("Saved to 9");

      } 
        else if (u8_key == '0'){
            writeLCD(0x01,0,0,1);
            sensorData[9] = f_temp;
            outStringLCD("Saved to 0");

      } 
        else if (u8_key == '*'){
            writeLCD(0x01,0,0,1);
            sensorData[10] = f_temp;
            outStringLCD("Saved to *");
      } 

Answer 1

最简单的解决方法是使用 switch...case 语句，例如

switch(u8_key)
{
    case '1':
        writeLCD(0x01,0,0,1); // clears LCD
        sensorData[0] = f_temp;
        outStringLCD("Saved to 1");
        break;

    case '2': 
        writeLCD(0x01,0,0,1); // clears LCD
        sensorData[1] = f_temp;
        outStringLCD("Saved to 2");
        break;
    ...

等等。请注意，您需要 break 语句来确保一次只命中一个 case。

编辑:请注意，Christian Gibbons 的解决方案更高效、更优雅，您应该使用它。仅当您需要对每种情况执行不同的操作时才应使用 switch 语句。