有没有办法替换字符串中的多个关键字并用自己的关键字包装它们？

Question

假设我有一个字符串：

typed = "need replace this ap"
str = "hello I need to replace this asap"

所以我想要的最终结果是：

newStr = "hello I <bold>need</bold> to <bold>replace</bold> <bold>this</bold> as<bold>ap</bold>"

请不要介意奇怪的语法。

我想知道订单是否重要，例如：

typed = "applicable app"
str = "the app is very applicable in many applications"

我希望的最终结果应该是：

newStr = "the <bold>app</bold> is very <bold>applicable</bold> in many <bold>app</bold>lications"

正确的？ 这可能吗？

Answer 1

嘿，如果你可以忽略这里奇怪的 HTML 语法，

然后我为你写了一个解决方案，

将此代码粘贴到dart 焊盘中

removeDuplicates(var typed, var str) {
  Map<String, String> m = new Map<String, String>();

  var n = typed.length;
  String ans = "";

  //for storing the "typed" string  (word by word) into a map "m" variable for later searching purpose
  String temp = "";
  int i = 0;
  for (i = 0; i < n; i++) {
    if (typed[i] == " ") {
      m[temp] = temp;
      temp = "";
    } else {
      temp = temp + typed[i];
    }
  }
  
  //for storing the last word of the string "typed", coz loop will never find a space in last of the string
  m[temp] = temp;

  // map variable loop for search from map "m" in the "str" string, and matching if the word is present or not
  var n2 = str.length;
  String temp2 = "";
  for (int j = 0; j < n2; j++) {
    if (str[j] == " ") {
      if (m.containsKey(temp2)) {
      } else {
        ans = ans + " " + temp2; //storing the "temp2" string into "ans" string, everytime it finds a space and if the string is not already present in the map "m"
      }
      temp2 = "";
    } else {
      temp2 = temp2 + str[j];
    }
  }

  //for searching for the last word of the string "str" in map "m", coz loop will never find a space in last of the string,
  if (m.containsKey(temp2)) {
  } else {
    ans = ans + " " + temp2;
  }

  return ans;
}

void main() {
  String typed = "need replace this ap";
  var str = "hello I need to replace this asap";
  String answer = removeDuplicates(typed, str);
  print(answer);
}

在这里，我创建了一个method removeDuplicates()来简化您的工作，您只需在您的method中传递这些string ，然后它将通过删除duplicates和一个新string return您所需的答案string 。

更新代码（显示 HTML 代码）：

removeDuplicates(var typed, var str) {
  Map<String, String> m = new Map<String, String>();

  var n = typed.length;
  String ans = "";

  //for storing the "typed" string  (word by word) into a map "m" variable for later searching purpose
  String temp = "";
  int i = 0;
  for (i = 0; i < n; i++) {
    if (typed[i] == " ") {
      m[temp] = temp;
      temp = "";
    } else {
      temp = temp + typed[i];
    }
  }

  //for storing the last word of the string "typed", coz loop will never find a space in last of the string
  m[temp] = temp;

  print(m);

  // map variable loop for search from map "m" in the "str" string, and matching if the word is present or not
  var n2 = str.length;
  String temp2 = "";
  for (int j = 0; j < n2; j++) {
    if (str[j] == " ") {
      if (m.containsKey(temp2)) {
        temp2 = "<bold>" + temp2 + "</bold> ";
        ans = ans + " " + temp2;
      } else {
        ans = ans +
            " " +
            temp2; //storing the "temp2" string into "ans" string, everytime it finds a space and if the string is not already present in the map "m"
      }
      temp2 = "";
    } else {
      temp2 = temp2 + str[j];
    }
  }

  //for searching for the last word of the string "str" in map "m", coz loop will never find a space in last of the string,
  if (m.containsKey(temp2)) {
    temp2 = "<bold>" + temp2 + "</bold> ";
    temp2 = "";
  } else {
    ans = ans + " " + temp2;
    temp2 = "";
  }

  return ans;
}

void main() {
  var typed = "applicable app";
  var str = "the app is very applicable in many applications";
  String answer = removeDuplicates(typed, str);
  print(answer);
}

更新 2 （感谢 PSKINK 的str.replaceAllMapped方法）

replaceWithBoldIfExists(String typed, String str) {
  var n = typed.length;
  List<String> searchList = new List<String>();

  String temp = "";
  int i = 0;
  for (i = 0; i < n; i++) {
    if (typed[i] == " ") {
      searchList.add(temp);
      temp = "";
    } else {
      temp = temp + typed[i];
    }
  }

  searchList.add(temp);

  String pat = searchList.join('|');
  final pattern = RegExp(pat);

  final replaced =
      str.replaceAllMapped(pattern, (m) => '<bold>${m.group(0)}</bold>');
  return replaced;
}

void main() {
  var typed = "need replace this ap";
  var str = "hello I need to replace this asap";
  print(replaceWithBoldIfExists(typed, str));
}