Question

我有一个edittext，例如我放入12345。我想检查前两个号码是否有＆＃39; sum> 0然后做一些事情。我不知道如何检查前两个元素＆＃39;总和。

if(pirinfouserid.getText().toString().indexOf(2)>0)
        Toast.makeText(getApplicationContext(), "ok",
                Toast.LENGTH_SHORT).show();
    else
        Toast.makeText(getApplicationContext(), "wrong",
                Toast.LENGTH_SHORT).show();

如果有人知道解决方案，请帮助我

由于

Answer 1

int num1=Integer.parseInt(pirinfouserid.getText().toString().charAt(0));
int num2=Integer.parseInt(pirinfouserid.getText().toString().charAt(1));
int sum=num1+num2;
if(sum>0)
    Toast.makeText(getApplicationContext(), "ok",
            Toast.LENGTH_SHORT).show();
else
    Toast.makeText(getApplicationContext(), "wrong",
            Toast.LENGTH_SHORT).show();

Answer 2

String input = pirinifouserid.getText().toString();

int firstNumber = Integer.parseInt(input.substring(0,1));
int secondNumber = Integer.parseInt(input.substring(1,2));
int sum = firstNumber + secondNumber;

if (sum > 0) ...

Answer 3

首先从用户输入的String输入前两个char：

String firstTwoDigit = s.substring(0, 
                  Math.min(pirinfouserid.getText().toString().length(), 1));

现在使用Find Sum of Digits in Java Algorithm得到两位数的总和：

// Parse String to Integer 
int sum = 0;
int digits = Integer.parseInt(firstTwoDigit);
while (digits != 0) {
 int lastdigit = digits % 10;
 sum += lastdigit;
 digits /= 10;
}
if(sum>0){
  // do your work
}else{
  // do your work
}

使用这种方式，您可以将数字和逻辑与其他代码分开，您可以在以后参数化这些代码来查找更多数字的总和。

在使用String.substring和Integer.parseInt之前，还要添加null和length检查字符串

Answer 4

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String input = pirinifouserid.getText().toString();
if(input.length()>2){
    try{
        int num1= Integer.parseInt(input.indexOf(0)); // Handle NumberFormatException
        int num2= Integer.parseInt(input.indexOf(1));// Handle NumberFormatException
        int sum = num1 + nm2;
        if (sum > 0){
            Toast.makeText(getApplicationContext(), "ok",
                Toast.LENGTH_SHORT).show();
        }else{
            Toast.makeText(getApplicationContext(), "wrong",
                Toast.LENGTH_SHORT).show();
        }
    }catch (NumberFormatException e){ 
        // DO what you think is correct. Probably show an error message 
    }
}

android edittext获取前两个输入值的总和

4 个答案: