how to check if str has an uppercase letter javascriptr code example
Example 1: javascript check if all capital letter
function isUpper(str) {
return !/[a-z]/.test(str) && /[A-Z]/.test(str);
}
isUpper("FOO");
isUpper("bar");
isUpper("123");
isUpper("123a");
isUpper("123A");
isUpper("A123");
isUpper("");
Example 2: check if letter is uppercase javascript
var strings = 'this iS a TeSt 523 Now!';
var i=0;
var character='';
while (i <= strings.length){
character = strings.charAt(i);
if (!isNaN(character * 1)){
alert('character is numeric');
}else{
if (character == character.toUpperCase()) {
alert ('upper case true');
}
if (character == character.toLowerCase()){
alert ('lower case true');
}
}
i++;
}