Counting Character Occurrences and Validating String Lengths in Javascript

In Javascript, determining the frequency of a character within a string is a common task. To count the occurrences, a straightforward method exists:

Consider the following string:

var mainStr = "str1,str2,str3,str4";

To ascertain the count of commas (,') within this string, we employ the match()` function:

console.log(("str1,str2,str3,str4".match(/,/g) || []).length); //logs 3

Alternatively, to count the number of strings created by splitting the main string along commas, we use a regular expression:

console.log(("str1,str2,str3,str4".match(new RegExp("str", "g")) || []).length); //logs 4

Moreover, in certain scenarios, validating the lengths of individual strings within the main string is necessary. If each string should not exceed 15 characters, this check can be implemented using a for loop:

for (let i = 0; i  15) {
        console.error(`String '${counts[i]}' exceeds the maximum length of 15 characters.`);
    }
}

By incorporating these techniques, you can effectively count character occurrences and validate string lengths in Javascript.