/*
This sample code is provided by Annsa Ltd. for information only.
*/

// Simple helper to return the "exMaxLen" attribute for
// the specified field. Using "getAttribute" won't work
// with Firefox.
function GetMaxLength(targetField)
{
return targetField.exMaxLen;
}

//
// Limit the text input in the specified field.
//
function LimitInput(targetField, sourceEvent)
{
    var isPermittedKeystroke;
    var enteredKeystroke;
    var maximumFieldLength;
    var currentFieldLength;
    var inputAllowed = true;
    var selectionLength = parseInt(GetSelectionLength(targetField));
    
    if ( GetMaxLength(targetField) != null )
    {
     // Get the current and maximum field length
     currentFieldLength = parseInt(targetField.value.length);
        maximumFieldLength = parseInt(GetMaxLength(targetField));

        // Allow non-printing, arrow and delete keys
enteredKeystroke = window.event ? sourceEvent.keyCode : sourceEvent.which;
        isPermittedKeystroke = ((enteredKeystroke < 32)                                // Non printing
                     ||(enteredKeystroke >= 33 && enteredKeystroke <= 40)    // Page Up, Down, Home, End, Arrow
                     ||(enteredKeystroke == 46));                           // Delete

        // Decide whether the keystroke is allowed to proceed
        if ( !isPermittedKeystroke )
        {
            if ( ( currentFieldLength - selectionLength ) >= maximumFieldLength ) 
            {
                inputAllowed = false;
            }
        }
        
        // Force a trim of the textarea contents if necessary
        if ( currentFieldLength > maximumFieldLength )
        {
            targetField.value = targetField.value.substring(0, maximumFieldLength)
        }
    } 
    
    sourceEvent.returnValue = inputAllowed;
    return (inputAllowed);
}

//
// Limit the text input in the specified field.
//
function LimitPaste(targetField, sourceEvent)
{
    var clipboardText;
    var resultantLength;
    var maximumFieldLength;
    var currentFieldLength;
    var pasteAllowed = true;
    var selectionLength = GetSelectionLength(targetField);

    if ( GetMaxLength(targetField) != null )
    {
     // Get the current and maximum field length
     currentFieldLength = parseInt(targetField.value.length);
        maximumFieldLength = parseInt(GetMaxLength(targetField));

        clipboardText = window.clipboardData.getData("Text");
        resultantLength = currentFieldLength + clipboardText.length - selectionLength;
        if ( resultantLength > maximumFieldLength)
        {
            if (currentFieldLength - selectionLength < maximumFieldLength)
            {
                targetField.value += clipboardText.substring(0, maximumFieldLength -(currentFieldLength - selectionLength));
            }
            pasteAllowed = false;
        }    
    }    
    
    sourceEvent.returnValue = pasteAllowed;
    return (pasteAllowed);
}

//
// Returns the number of selected characters in 
// the specified element
//
function GetSelectionLength(targetField)
{
    if ( targetField.selectionStart == undefined )
    {
        return document.selection.createRange().text.length;
    }
    else
    {
        return (targetField.selectionEnd - targetField.selectionStart);
    }
} /* This sample code is provided by Annsa Ltd. for information only. */ // Simple helper to return the "exMaxLen" attribute for // the specified field. Using "getAttribute" won't work // with Firefox. function GetMaxLength(targetField) { return targetField.exMaxLen; } // // Limit the text input in the specified field. // function LimitInput(targetField, sourceEvent) { var isPermittedKeystroke; var enteredKeystroke; var maximumFieldLength; var currentFieldLength; var inputAllowed = true; var selectionLength = parseInt(GetSelectionLength(targetField)); if ( GetMaxLength(targetField) != null ) { // Get the current and maximum field length currentFieldLength = parseInt(targetField.value.length); maximumFieldLength = parseInt(GetMaxLength(targetField)); // Allow non-printing, arrow and delete keys enteredKeystroke = window.event ? sourceEvent.keyCode : sourceEvent.which; isPermittedKeystroke = ((enteredKeystroke < 32) // Non printing ||(enteredKeystroke >= 33 && enteredKeystroke <= 40) // Page Up, Down, Home, End, Arrow ||(enteredKeystroke == 46)) // Delete // Decide whether the keystroke is allowed to proceed if ( !isPermittedKeystroke ) { if ( ( currentFieldLength - selectionLength ) >= maximumFieldLength ) { inputAllowed = false; } } // Force a trim of the textarea contents if necessary if ( currentFieldLength > maximumFieldLength ) { targetField.value = targetField.value.substring(0, maximumFieldLength) } } sourceEvent.returnValue = inputAllowed; return (inputAllowed); } // // Limit the text input in the specified field. // function LimitPaste(targetField, sourceEvent) { var clipboardText; var resultantLength; var maximumFieldLength; var currentFieldLength; var pasteAllowed = true; var selectionLength = GetSelectionLength(targetField); if ( GetMaxLength(targetField) != null ) { // Get the current and maximum field length currentFieldLength = parseInt(targetField.value.length); maximumFieldLength = parseInt(GetMaxLength(targetField)); clipboardText = window.clipboardData.getData("Text"); resultantLength = currentFieldLength + clipboardText.length - selectionLength; if ( resultantLength > maximumFieldLength) { pasteAllowed = false; } } sourceEvent.returnValue = pasteAllowed; return (pasteAllowed); } // // Returns the number of selected characters in // the specified element // function GetSelectionLength(targetField) { if ( targetField.selectionStart == undefined ) { return document.selection.createRange().text.length; } else { return (targetField.selectionEnd - targetField.selectionStart); } }