How can I perform a str_replace in JavaScript, replacing text in JavaScript?

Question

I want to use str_replace or its similar alternative to replace some text in JavaScript.

var text = \"this is some sample text that i want to re         


        

Answer 1

Added a method replace_in_javascript which will satisfy your requirement. Also found that you are writing a string "new_text" in document.write() which is supposed to refer to a variable new_text.

let replace_in_javascript= (replaceble, replaceTo, text) => {
  return text.replace(replaceble, replaceTo)
}

var text = "this is some sample text that i want to replace";
var new_text = replace_in_javascript("want", "dont want", text);
document.write(new_text);

Answer 2

var new_text = text.replace("want", "dont want");

Answer 3

In Javascript, replace function available to replace sub-string from given string with new one. Use:

var text = "this is some sample text that i want to replace";
var new_text = text.replace("want", "dont want");
console.log(new_text);

You can even use regular expression with this function. For example, if want to replace all occurrences of , with ..

var text = "123,123,123";
var new_text = text.replace(/,/g, ".");
console.log(new_text);

Here g modifier used to match globally all available matches.

Answer 4

Use JS String.prototype.replace first argument should be Regex pattern or String and Second argument should be a String or function.

str.replace(regexp|substr, newSubStr|function);

Ex:

var str = 'this is some sample text that i want to replace'; var newstr = str.replace(/want/i, "dont't want"); document.write(newstr); // this is some sample text that i don't want to replace

Answer 5

JavaScript has replace() method of String object for replacing substrings. This method can have two arguments. The first argument can be a string or a regular expression pattern (regExp object) and the second argument can be a string or a function. An example of replace() method having both string arguments is shown below.

var text = 'one, two, three, one, five, one';
var new_text = text.replace('one', 'ten');
console.log(new_text)  //ten, two, three, one, five, one

Note that if the first argument is the string, only the first occurrence of the substring is replaced as in the example above. To replace all occurrences of the substring you need to provide a regular expression with a g (global) flag. If you do not provide the global flag, only the first occurrence of the substring will be replaced even if you provide the regular expression as the first argument. So let's replace all occurrences of one in the above example.

var text = 'one, two, three, one, five, one';
var new_text = text.replace(/one/g, 'ten');
console.log(new_text)  //ten, two, three, ten, five, ten

Note that you do not wrap the regular expression pattern in quotes which will make it a string not a regExp object. To do a case insensitive replacement you need to provide additional flag i which makes the pattern case-insensitive. In that case the above regular expression will be /one/gi. Notice the i flag added here.

If the second argument has a function and if there is a match the function is passed with three arguments. The arguments the function gets are the match, position of the match and the original text. You need to return what that match should be replaced with. For example,

var text = 'one, two, three, one, five, one';
var new_text = text.replace(/one/g, function(match, pos, text){
return 'ten';
});
console.log(new_text) //ten, two, three, ten, five, ten

You can have more control over the replacement text using a function as the second argument.

Answer 6

You can use

text.replace('old', 'new')

And to change multiple values in one string at once, for example to change # to string v and _ to string w:

text.replace(/#|_/g,function(match) {return (match=="#")? v: w;});