If substring in string, remove it through the end from string

Question

I'm trying to figure out how to do the following with javascript:
If a substring is in the string, remove from the beginning of the substring till the end of the string from the string.

For example (pseudocode):

var mySub = 'Foo'
var myString = 'testingFooMiscText'
var myString2 = 'testingMisctext'

var myStringEdit = //myString - (Foo till end myString)
var myString2Edit = myString2 //(cause no Foo in it)

So should the edited "testingFooMiscText" end up as "testing" or as "FooMiscText"? — yoozer8, Aug 11 '11 at 20:43
@dmr To clarify, you would want `'testing'` from `myString`, correct? — Charmander, Aug 11 '11 at 20:44
So, if 'Foo' is in the string, you want to truncate the string starting at Foo? Is that what you're asking? — FishBasketGordo, Aug 11 '11 at 20:45
A super awesome tidbit for indexOf: Use ~ as invert: if(~index) str = str.substr(index) -awesome read: http://timmywillison.com/pres/operators/#bitwise-operators - check out preceding slides for more context. — David Hobs, Sep 09 '12 at 05:17

hungryMind · Accepted Answer · 2011-08-12T07:52:45.930

6

var index = str.indexOf(str1);
if(index != -1)
    str = str.substr(index)

edited Aug 12 '11 at 07:52

answered Aug 11 '11 at 20:46

hungryMind

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score 6 · Answer 2 · answered Aug 11 '11 at 20:47

6

If I understand what you're asking, you'll want to do this:

function replaceIfSubstring(original, substr) {
    var idx = original.indexOf(substr);
    if (idx != -1) {
        return original.substr(idx);
    } else {
        return original;
    }
}

answered Aug 11 '11 at 20:47

FishBasketGordo

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+1 Only truncates if substring in original, else returns original. – Charmander Aug 11 '11 at 20:55

score 2 · Answer 3 · answered Aug 11 '11 at 20:45

If you want "testingFooMiscText" to end up as "testing", use

word = word.substring(0, word.indexOf("Foo"));

If you want "testingFooMiscText" to end up as "FooMiscText", use

word = word.substring(word.indexOf("Foo"));

You may need a +/- 1 after the indexOf() to adjust the start/end of the string

score 2 · Answer 4 · answered Aug 11 '11 at 20:46

2

myString.substring(0, myString.indexOf(mySub))

answered Aug 11 '11 at 20:46

Charmander

196
1
14

3

However, mySub might not be in myString...so then the substring function won't work. – dmr Aug 11 '11 at 20:49
Put it inside an if statement. Here is a question on checking to see if a string contains another. [link](http://stackoverflow.com/questions/1789945/javascript-string-contains) – Charmander Aug 11 '11 at 20:50
1

This doesn't return the original string if the substring isn't found. I believe that's what the OP wants. – FishBasketGordo Aug 11 '11 at 20:52
Fair enough, @FishBasketGordo. – Charmander Aug 11 '11 at 20:54

score 0 · Answer 5 · answered Aug 11 '11 at 20:45

0

var newString = mystring.substring(mystring.indexOf(mySub));

answered Aug 11 '11 at 20:45

Paul

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score 0 · Answer 6 · answered Aug 11 '11 at 20:46

0

This should do the trick.

var myString = 'testingFooMiscText'
myString.substring(myString.indexOf('Foo'))  //FooMiscText
myString.substring(myString.indexOf('Bar'))  //testingFooMiscText

answered Aug 11 '11 at 20:46

Jeff

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score -2 · Answer 7 · edited May 23 '17 at 17:03

-2

I used following code to eliminate fakefile from file Name and it worked.

function confsel()
{
    val = document.frm1.fileA.value;
    value of val comes like C:\fakepath\fileName
    var n = val.includes("fakepath");
    if(n)
    {
        val=val.substring(12);
    } 
}

edited May 23 '17 at 17:03

Brunner

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answered May 23 '17 at 16:10

Arun Sule

1

If substring in string, remove it through the end from string

7 Answers7