C # regular expression to determine whether it is a special character

In fact, there are two ways to judge whether it is a special character:

The first idea is to list all special characters and determine that the target string contains special characters.

public bool IsSpecialChar(string str){
    Regex regExp = new Regex("[ \\[ \\] \\^ \\-_*×――(^)$%~!＠@＃#$…&%￥—+=<>《》!！??？:：•`·、。，；,.;/\'\"{}（）‘’“”-]");
    if(regExp.IsMatch(str)){
        return true;
    }
    return false;
}

The problem with this line of thinking is that you ca n’t miss any special character, or the code has a bug

The second idea is to list all characters that are not special characters and determine whether the target string does not contain these characters.

public bool IsSpecialChar(string str){
    Regex regExp = new Regex("[^0-9a-zA-Z\u4e00-\u9fa5]");
    if(regExp.IsMatch(str)){
        return true;
    }
    return false;
}

The advantage of this way of thinking is that as long as the Chinese characters, letters, numbers and other characters that are not special characters are listed.