Js controls the number of input strings in textarea. Press the mouse and hold it up to determine the number of input characters. jstextarea

Js controls the number of input strings in textarea. Press the mouse and hold it up to determine the number of input characters. jstextarea

[Html code]

<Table>

<Tr>

<Td width = "150"> text message content: </td>

<Td>

<Textarea name = "message" cols = "96" rows = "5" onKeyDown = "textCounter (message, remLen, 65 );"

OnKeyUp = "textCounter (message, remLen, 65);"> </textarea>

<Td>

</Tr>

<Tr> <td> </td>

<Td> You can also enter <input name = "remLen" type = "text" value = "65" size = "5" readonly = "readonly"> characters, each text message can contain up to <strong> 65 </strong> characters </td>

</Tr>

</Table>

[Corresponding js Code]

<Script>
Function textCounter (field, countfield, maxlimit ){
If (field. value. length> maxlimit)
Field. value = field. value. substring (0, maxlimit );
Else
Countfield. value = maxlimit-field. value. length;
}
</Script>

Js question: How does one specify the number of characters in a string?

Check whether this meets your requirements.

Public class Test {

Public static void main (String [] args ){
Test t = new Test ();
String s = "wohoeniohoaoohah ";
String c = "o ";
Int x = t. getNum (s, c );
System. out. println (x );
}
Public int getNum (String s, String c) {// s is the original String. c is the String we are looking for. Of course, it can be a character.
Int x = s. indexOf (c); // checks whether C exists in S! If x =-1, it indicates no.
Int sum = 0; // number of occurrences!
While (x! =-1 ){
Sum ++;
S = s. replaceFirst (c, ""); // replace C with "". recyclically find the next C
X = s. indexOf (c );
}
Return sum;
}
}

How can I use JavaScript to limit the number of characters in multiple lines of text fields? to limit the number of characters in a single line of text box, it cannot appear again after entering the specified number of characters

In this way:
<Textarea oninput = "s ()" onpropertychange = "s ()"> </textarea>
Function s (){
Var leng = number of characters to limit
If (this. value. lengtg> = leng ){
// Add a limit to achieve stronger results
Event. returnValue = false; // when the number of words reaches the specified value, any buttons are invalid.
// Truncate the string
This. value = this. value. substring (0, leng );
}
}

Because onpropertychange is only valid in IE, and oninput is valid in most browsers, the two are used together.