char不在java分数计算器中工作

Question

即使输入有下划线，此代码也会返回false。   输入将类似于1_3 / 4 + 3并将返回4_3 / 4

  String[] Separated = fraction.split(" "); //Splits the tokens up
  String firstToken = Separated[0]; // I created this to try to troubleshoot
  boolean Mixed = true; //This would determine how much I will need to split up
  for(int i = 0; i < firstToken.length(); i++) {
     if(firstToken.charAt(i) == '_') { 
        Mixed = true;
     }
     else {
        Mixed = false;
     }
  }

Answer 1

您可以使用＆＃34;包含＆＃34;而不是循环：

boolean mixed = firstToken.contains("_");

请在java中使用小写变量名。

Answer 2

如果您想获得下划线字符的位置，我们的代码可以快速修复：

String firstToken = "_"; // I created this to try to troubleshoot
    boolean Mixed = true; //This would determine how much I will need to split up
    int i;
    for(i = 0; i < firstToken.length(); i++) {
        if(firstToken.charAt(i) == '_') {
            Mixed = true;
            break;
        }
        else {
            Mixed = false;
        }
    }
    //i gives the index of underscore

虽然有更简洁的方法可以做到这一点。 这应该得到下划线的索引

    String firstToken = Seperated[0]; // I created this to try to troubleshoot     
    int index==firstToken.indexOf('_');