I'm trying to change subindex of string array but it's not modifing.There is the jsbin link.
function LetterCapitalize(str) {
var arr = str.split(" ");
var nstr = "";
for (var i = 0; i < arr.length; i++) {
var ltr = arr[i][0];
console.log('ltr: ' + ltr.toUpperCase());
arr[i][0] = ltr.toUpperCase();
nstr += arr[i] + " ";
}
str = nstr.trim();
console.log("result: " + str);
return str;
}
LetterCapitalize("hello world");You could try something like the following:
function LetterCapitalize(str) {
var arr = str.split(" ");
var nstr = "";
for(var i=0; i<arr.length; i++){
arr[i] = arr[i][0].toUpperCase()+arr[i].slice(1);
nstr+= arr[i] + " ";
}
str = nstr.trim();
console.log("result: " + str);
return str;
}
console.log(LetterCapitalize("hello world"));The line that does the difference is the following:
arr[i] = arr[i][0].toUpperCase() + arr[i].slice(1);
What we are doing here is to capitalize the first letter of the string at arr[i] and then concatenate the capitalized letter with the rest letters.
return arr.join(' ');That's because (https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String#Character_access):
For character access using bracket notation, attempting to delete or assign a value to these properties will not succeed. The properties involved are neither writable nor configurable.
I.e. strings are immutable.
You could as well just use string.replace matching the first char in each word, using a callback function to upper case the character.
Something like this.
var str = "hello world";
var newStr = str.replace(/\b(\w)/g, function(chr) {
return chr.toUpperCase()
})
console.log(newStr)