Lets say I have the following string in my javascript code:
var myText = 'Hello %1. How are you %2?';
Now I would like to inject something in place of %1 and %2 in the above string. I can do:
var result = myText.replace('%1', 'John').replace('%2', 'today');
I wonder if there is a better way of doing than calling 2 times the replace function.
Thanks.
How about a little format helper? That's basically what you need:
function format(str, arr) {
return str.replace(/%(\d+)/g, function(_,m) {
return arr[--m];
});
}
var myText = 'Hello %1. How are you %2?';
var values = ['John','today'];
var result = format(myText, values);
console.log(result); //=> "Hello John. How are you today?"
{1} with a slightly different regex. It works for all my needs. But yes, there are libraries for more robust solutions.
Try this sample
function setCharAt(str,chr,rep) {
var index = -1;
index= str.indexOf(chr);
var len= chr.length;
if(index > str.length-1) return str;
return str.substr(0,index) + rep + str.substr(index+len);
}
var myText = 'Hello %1. How are you %2?';
var result = setCharAt(myText,"%1","John");
var result = setCharAt(result,"%2","today");
alert(result);
This is meant just as a complex comment to elclarns' great answer, suggesting these alternatives:
String.prototypeargumentsThe function can be altered to
String.prototype.format = function() {
var args=arguments;
return this.replace(/%(\d+)/g, function(_,m) {
return args[--m];
});
}
And called this way
var result = "I am %1, %2 years old %1".format("Jan",32);
// I am Jan, 32 years old Jan
