I am creating a live content editor for an element using textarea, but its output isn't like what the expected if the inputted value is symbol like > or < or mix up of those symbols and texts, instead of just texts, then it will not replacing instead of doubled it up.
Here is the Fiddle
And here is the jquery codes:
$("#changer").on("change keyup paste", function () {
// get current element
var thehtml = $("#tochange").html();
var thetext = $("#tochange").contents().filter(function () {
return this.nodeType === 3;
}).text().trim();
var thechange = $(this).val();
// if has element, then keep it, add text and put back
var thepurehtml = thehtml.replace(thetext, "");
var theoutput = thechange;
if ($.trim(thepurehtml) != '') {
var theoutput = thechange + thepurehtml;
}
$("#tochange").html("").html(theoutput);
return;
});
What's causing it and how to fix it up?
PS: I need to have the functionality of this line var theoutput = thechange + thepurehtml; because it is sometimes the edited element have html element other than just a blank or text node.
However i am going to delete this answer, As i don't have enough reputation to comment i am posting as answer.
So #SoursopTree, what you actually want to achieve?
What i found is when you enter < or > the line $.trim(thepurehtml) is returning empty string (null) and null!='', so the next statement var theoutput = thechange + thepurehtml; here thechange=> and thepurehtml=>. so you are getting two symbols instead of one.
You said you need to have the functionality of this line var theoutput = thechange + thepurehtml;
I am working on javascript code that parses a tab delimited document. In order to facilitate searching I need to convert those properties that are a number to a float. However, mixed fields (like an address) should maintain the status of a String.
for(var i2=0;i2<line1.length;i2++){
var test = local[i2];
if(! (typeof test === 'undefined')){
test = test.trim();
};
var parsed = parseFloat(test);
if(!isNaN(parsed)){
if(line1[i2] === "Site Address")
console.log("Number before:"+local[i2]+" After:"+parsed);
object[line1[i2]]=parsed;
}
else{
if(line1[i2] === "Site Address")
console.log("before:"+local[i2]+" After:"+test);
object[line1[i2]]=test;
}
}
This seems to work ok unless there are both numbers and chars like the following....
Number before:1752 E MAIN ST After:1752
Is there a way to do this where the above is not seen as explicitly a number?
You can use the unary + operator:
var parsed = +test;
The parseFloat() function is OK with strings that start with a valid number that's followed by non-numeric stuff, as you've discovered.
If that seems too "hackery" you can also use the Number constructor:
var parsed = Number( test );
You haven't provided very much test data, so answers may not be very good. You can try using a regular expression so that only things that look like numbers are treated as numbers, e.g.
var isNum = /^\d+(\.\d+)?$/;
var test = line1[i2];
parsed = isNum.test(test)? parseFloat(test) : test;
The variable "test" would probaby be better named "item" or "value" or similar.
This is clearly a RTFM issue, but after I did so repeatedly I just can't get the damn thing to work so there are times when asking for help makes sense:
var text = "KEY:01 VAL:1.10,KEY:02 VAL:2.20,KEY:03 VAL:3.30";
var pattern = '/KEY:(\S+) VAL:([^,]+)/g';
//var pattern = '/KEY:(\S+) VAL:(.?+)(?:(?=,KEY:)|$)/g';
//var pattern = '/KEY:(\S+) VAL:(.+)$/g';
//pattern.compile(pattern);
var kv = null;
var row = 0, col = 0;
while((kv = pattern.exec(text) != null))
{
row = kv[1].charAt(0) - '0';
col = kv[1].charAt(1) - '0';
e = document.getElementById('live').rows[row].cells;
e[col].innerHTML = kv[2].slice(0, kv[2].indexOf(","));
}
kv[1] is supposed to give "01"
kv[2] is supposed to give "1.10"
...and of course kv[] should list all the values of 'text'
to fill the table called 'live'.
But I can't get to have pattern.exec() succeed in doing that.
Where is the glitch?
First, the delimiters for the RegExp should be /s, there's no need to put them in ' delimiters. i.e. to get your exec to run properly you should have:
var pattern = /KEY:(\S+) VAL:([^,]+)/g;
Second, you're assigning a boolean to kv which you don't want. The while will obviously only evaluate to true if it's not null so that's redundant. Instead you just need:
while (kv = pattern.exec(text)) {
That should get your code to work as you desire.
the syntax for pattern objects doesn't include quoting, such as:
var pattern=/KEY:(\S+) VAL:([^,]+)/g;
http://www.w3schools.com/jsref/jsref_regexp_exec.asp
It should be
var pattern = /KEY:(\S+) VAL:([^,]+)/g;
http://www.regular-expressions.info/ is a good place to start with.
I have a question. I'm wanting to run a basic function in Javascript which takes an input field from a form and checks the very first character to ensure it does not have a £ sign (GBP) infront of the value
I can't seem to find the right code anywhere to do this? - Anyone have any idea's... I'm a bit of a noob to all this programming to be honest so any help would be gratefully received.
If you have an input field and you want to get it's value and check the first character of the value, you can do so like this:
<input type="text" id="price">
var str = document.getElementById("price").value;
if (str.charAt(0) == "£") {
// do whatever you need to do if there's a £ sign at the beginning
}
If the £ sign isn't supposed to be there, perhaps you could just safely remove it or ignore it rather than make the end user remove it like this:
var el = document.getElementById("price");
if (el.value.charAt(0) == "£") {
el.value = el.value.substr(1);
}
Assuming your HTML is something like this:
<input type="text" id="my_input" />
<button onClick="checkInput();">Check input</button>
Then you want to build your script like this:
function checkInput() {
var inp = document.getElementById('my_input'); // get the input field
inp = inp.value; // get the value
inp = inp.charAt(0); // get the first character
if( inp == "£") {
// do something
}
}
That can be condensed into:
function checkInput() {
if( document.getElementById('my_input').value.charAt(0) == "£") {
// do something
}
}
The trick to any code-writing is breaking a big problem into smaller ones. Step by step.
charAt should do it
var str = "Foo";
var firstChar = str.charAt(0);
How can I convert a JavaScript string value to be in all lowercase letters?
Example: "Your Name" to "your name"
var lowerCaseName = "Your Name".toLowerCase();
Use either toLowerCase or toLocaleLowerCase methods of the String object. The difference is that toLocaleLowerCase will take current locale of the user/host into account. As per § 15.5.4.17 of the ECMAScript Language Specification (ECMA-262), toLocaleLowerCase…
…works exactly the same as toLowerCase
except that its result is intended to
yield the correct result for the host
environment’s current locale, rather
than a locale-independent result.
There will only be a difference in the
few cases (such as Turkish) where the
rules for that language conflict with
the regular Unicode case mappings.
Example:
var lower = 'Your Name'.toLowerCase();
Also note that the toLowerCase and toLocaleLowerCase functions are implemented to work generically on any value type. Therefore you can invoke these functions even on non-String objects. Doing so will imply automatic conversion to a string value prior to changing the case of each character in the resulting string value. For example, you can apply toLowerCase directly on a date like this:
var lower = String.prototype.toLowerCase.apply(new Date());
and which is effectively equivalent to:
var lower = new Date().toString().toLowerCase();
The second form is generally preferred for its simplicity and readability. On earlier versions of IE, the first had the benefit that it could work with a null value. The result of applying toLowerCase or toLocaleLowerCase on null would yield null (and not an error condition).
Yes, any string in JavaScript has a toLowerCase() method that will return a new string that is the old string in all lowercase. The old string will remain unchanged.
So, you can do something like:
"Foo".toLowerCase();
document.getElementById('myField').value.toLowerCase();
toLocaleUpperCase() or lower case functions don't behave like they should do. For example, on my system, with Safari 4, Chrome 4 Beta, and Firefox 3.5.x, it converts strings with Turkish characters incorrectly. The browsers respond to navigator.language as "en-US", "tr", "en-US" respectively.
But there isn't any way to get user's Accept-Lang setting in the browser as far as I could find.
Only Chrome gives me trouble although I have configured every browser as tr-TR locale preferred. I think these settings only affect the HTTP header, but we can't access to these settings via JavaScript.
In the Mozilla documentation it says "The characters within a string are converted to ... while respecting the current locale. For most languages, this will return the same as ...". I think it's valid for Turkish, and it doesn't differ if it's configured as en or tr.
In Turkish it should convert "DİNÇ" to "dinç" and "DINÇ" to "dınç" or vice-versa.
Just an example for toLowerCase(), toUpperCase() and a prototype for the not yet available toTitleCase() or toProperCase():
String.prototype.toTitleCase = function() {
return this.split(' ').map(i => i[0].toUpperCase() + i.substring(1).toLowerCase()).join(' ');
}
String.prototype.toPropperCase = function() {
return this.toTitleCase();
}
var OriginalCase = 'Your Name';
var lowercase = OriginalCase.toLowerCase();
var upperCase = lowercase.toUpperCase();
var titleCase = upperCase.toTitleCase();
console.log('Original: ' + OriginalCase);
console.log('toLowerCase(): ' + lowercase);
console.log('toUpperCase(): ' + upperCase);
console.log('toTitleCase(): ' + titleCase);
I paid attention that lots of people are looking for strtolower() in JavaScript. They are expecting the same function name as in other languages, and that's why this post is here.
I would recommend using a native JavaScript function:
"SomE StriNg".toLowerCase()
Here's the function that behaves exactly the same as PHP's one (for those who are porting PHP code into JavaScript)
function strToLower (str) {
return String(str).toLowerCase();
}
Methods or functions: toLowerCase() and toUpperCase()
Description: These methods are used to cover a string or alphabet from lowercase to uppercase or vice versa. E.g., "and" to "AND".
Converting to uppercase:
Example code:
<script language=javascript>
var ss = " testing case conversion method ";
var result = ss.toUpperCase();
document.write(result);
</script>
Result: TESTING CASE CONVERSION METHOD
Converting to lowercase:
Example Code:
<script language=javascript>
var ss = " TESTING LOWERCASE CONVERT FUNCTION ";
var result = ss.toLowerCase();
document.write(result);
</script>
Result: testing lowercase convert function
Explanation: In the above examples,
toUpperCase() method converts any string to "UPPER" case letters.
toLowerCase() method converts any string to "lower" case letters.
Note that the function will only work on string objects.
For instance, I was consuming a plugin, and was confused why I was getting a "extension.tolowercase is not a function" JavaScript error.
onChange: function(file, extension)
{
alert("extension.toLowerCase()=>" + extension.toLowerCase() + "<=");
Which produced the error "extension.toLowerCase is not a function". So I tried this piece of code, which revealed the problem!
alert("(typeof extension)=>" + (typeof extension) + "<=");;
The output was "(typeof extension)=>object<=" - so aha, I was not getting a string var for my input. The fix is straightforward though - just force the darn thing into a String!:
var extension = String(extension);
After the cast, the extension.toLowerCase() function worked fine.
Option 1: Using toLowerCase()
var x = 'ABC';
x = x.toLowerCase();
Option 2: Using your own function
function convertToLowerCase(str) {
var result = '';
for (var i = 0; i < str.length; i++) {
var code = str.charCodeAt(i);
if (code > 64 && code < 91) {
result += String.fromCharCode(code + 32);
} else {
result += str.charAt(i);
}
}
return result;
}
Call it as:
x = convertToLowerCase(x);
Simply use JS toLowerCase()
let v = "Your Name"
let u = v.toLowerCase(); or
let u = "Your Name".toLowerCase();
const str = 'Your Name';
// convert string to lowercase
const lowerStr = str.toLowerCase();
// print the new string
console.log(lowerStr);
In case you want to build it yourself:
function toLowerCase(string) {
let lowerCaseString = "";
for (let i = 0; i < string.length; i++) {
// Find ASCII charcode
let charcode = string.charCodeAt(i);
// If uppercase
if (charcode > 64 && charcode < 97) {
// Convert to lowercase
charcode = charcode + 32
}
// Back to char
let lowercase = String.fromCharCode(charcode);
// Append
lowerCaseString = lowerCaseString.concat(lowercase);
}
return lowerCaseString
}
You can use the in built .toLowerCase() method on JavaScript strings. Example:
var x = "Hello";
x.toLowerCase();
Try this short way:
var lower = (str+"").toLowerCase();
Try
<input type="text" style="text-transform: uppercase"> <!-- uppercase -->
<input type="text" style="text-transform: lowercase"> <!-- lowercase -->
Demo - JSFiddle