How can I remove all the left space without removing between & the right space of the string? And also when I changed the value of str the result will be the same. Only the left space will be removed.
function trimLeftSpace() {
var str = " Angry Bird ";
var splitTrim = str.split('');
var trimStr = "";
for (var index = 0; index < splitTrim.length; index++) { //trim left space
if(splitTrim[index] != " ") {
trimStr += str[index];
}
}
return trimStr;
}
To trim the beginning of the string, use a simple regex
to replace the whitespaces in the beginning of the string:
var str = " Angry Bird "; function trimLeftSpace(str) { return str.replace(/^\\s+/, ''); } console.log('"' + trimLeftSpace(str) + '"');
Or just use .trimStart()
:
var str = " Angry Bird "; function trimLeftSpace(str) { return str.trimStart(); } console.log('"' + trimLeftSpace(str) + '"');
Your current solution creates a new string which contains all the non-space characters of the original string, you need to stop looking for spaces as soon as you find a non-space character. Here is an example:
function trimLeftSpace(str) { var doneTrimming = false var ret = "" for (var index = 0; index < str.length; index++) { if(str[index] !== ' '){ doneTrimming = true } if(doneTrimming){ ret += str[index] } } return ret; } var result = trimLeftSpace(" Angry Bird "); console.log("|"+result+"|");
You could try a regex replacement:
var str = " Angry Bird "; str = str.replace( new RegExp("^\\\\s+", "gm"),""); console.log('"' + str + '"');
This will remove all whitespace on the left of the string:
function trimLeftSpace(str) { var result = ""; for(var i = 0; i < str.length; i++) { if(str[i] != " ") { return str.slice(i); break; } else { result += str[i]; } } return result; } console.log(trimLeftSpace(" Angry Birds Angry Birds"));
Try this
function trimLeftSpace(str) {
return str.replace(/\s+$/, '')
}
var result = trimLeftSpace(" Angry Bird ");
console.log("|"+result+"|");
If you want to use a function instead of regex solutions from the other answers, then make a function that looks for the first non-space character, then use slice
to cut only the part of the string that's after it:
function customTrim(str) { for(var i = 0; i < str.length; i++) { if(str.charAt(i) !== " ") { return str.slice(i); } } } var res = customTrim(" Snake Shot "); console.log('"' + res + '"');
Notes:
' '
. If you want to look for tabs '\\t'
, newlines '\\n'
, ... then just add them to the if
test (sperate them with &&
). undefined
is returned, if you don't want that then just return an empty string at the bottom of the function to make it the default return value.
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