how to check if first letter is uppercase javascript code example
Example 1: javascript capitalize words
//capitalize only the first letter of the string.
function capitalizeFirstLetter(string) {
return string.charAt(0).toUpperCase() + string.slice(1);
}
//capitalize all words of a string.
function capitalizeWords(string) {
return string.replace(/(?:^|\s)\S/g, function(a) { return a.toUpperCase(); });
};
Example 2: javascript check if all capital letter
function isUpper(str) {
return !/[a-z]/.test(str) && /[A-Z]/.test(str);
}
isUpper("FOO"); //true
isUpper("bar"); //false
isUpper("123"); //false
isUpper("123a"); //false
isUpper("123A"); //true
isUpper("A123"); //true
isUpper(""); //false
Example 3: javascript capitalize first letter
const lower = 'this is an entirely lowercase string';
const upper = lower.charAt(0).toUpperCase() + lower.substring(1);
Example 4: capitalise first letter js
const string = "tHIS STRING'S CAPITALISATION WILL BE FIXED."
const string = string.charAt(0).toUpperCase() + string.slice(1)