www.webdeveloper.com
Results 1 to 6 of 6

Thread: Allow user to add negative number

  1. #1
    Join Date
    Jan 2013
    Posts
    10

    Allow user to add negative number

    I would like to modify this javascript so I can input negative number -3 to -1 if useNegativeScale is TRUE... Below is the javascript:

    Code:
    	function testValidity(box, maxScale, useNA, useNegativeScale, nextBox)
    	{
    		var nScale, minScale, tab, oldValue, space, backspace, del, minNumPad, maxNumPad;
    		oldValue = box.value;
    		
    		tab = 9;
    		space = 32;
    		backspace = 8;
    		del = 46;
    		
    		if (useNegativeScale == "True")
    		{
    			var dash, subtract, hyphen;
    			
    			dash = 189;
    			subtract = 109;
    			hyphen = 173;
    			nScale = 78;
    			
    			minScale = 48;
    			minNumPad = 96;
    			
    			maxNumPad = minNumPad + (maxScale - minScale);
    			
    			if(event.keyCode == space || event.keyCode == backspace || event.keyCode == del)
    			{
    				event.cancelBubble = true;
    				event.returnValue = false;
    				box.value = "";
    			}
    			else if(event.keyCode == nScale && useNA == "True")
    			{
    				event.cancelBubble = true;
    				event.returnValue = false;
    				box.value = "n";
    			}
    			else if(event.keyCode == dash || event.keyCode == subtract || event.keyCode == hyphen)
    			{
    				event.cancelBubble = true;
    				event.returnValue = false;
    				box.value = "-";
    			}
    			else if((event.keyCode >= minScale && event.keyCode <= maxScale) || (event.keyCode >= minNumPad && event.keyCode <= maxNumPad))
    			{
    				if (event.keyCode > maxScale)
    				{
    					box.value = event.keyCode - 96;
    				}
    				else
    				{
    					box.value = event.keyCode - 48;
    				}
    				
    				eval("document.all." + nextBox).focus();
    				event.cancelBubble = true;
    				event.returnValue = false;
    			}
    			else if (event.keyCode != tab)
    			{
    				event.cancelBubble = true;
    				event.returnValue = false;
    				box.value = oldValue;
    				self.alert("<%= pageVals.Item("errors")("invalidvalue") %>");
    				box.select();
    			}
    		}
    		else
    		{
    			minScale = 49;
    			minNumPad = 97;
    			nScale = 78;
    			
    			maxNumPad = minNumPad + (maxScale - minScale);
    			
    			if(event.keyCode == space || event.keyCode == backspace || event.keyCode == del)
    			{
    				event.cancelBubble = true;
    				event.returnValue = false;
    				box.value = "";
    			}
    			else if(event.keyCode == nScale && useNA == "True")
    			{
    				event.cancelBubble = true;
    				event.returnValue = false;
    				box.value = "n";
    			}
    			else if((event.keyCode >= minScale && event.keyCode <= maxScale) || (event.keyCode >= minNumPad && event.keyCode <= maxNumPad))
    			{
    				if (event.keyCode > maxScale)
    				{
    					box.value = event.keyCode - 96;
    				}
    				else
    				{
    					box.value = event.keyCode - 48;
    				}
    				
    				eval("document.all." + nextBox).focus();
    				event.cancelBubble = true;
    				event.returnValue = false;
    			}
    			else if(event.keyCode != tab)
    			{
    				event.cancelBubble = true;
    				event.returnValue = false;
    				box.value = oldValue;
    				self.alert("<%= pageVals.Item("errors")("invalidvalue") %>");
    				box.select();
    			}
    		}
    	}

    Here is the HTML:

    Code:
    <td style="text-align: center;"><input type="text" onFocus="getElement('TR<%= i %>').className = 'Highlite<%= TRClass %>';" onBlur="getElement('TR<%= i %>').className = '<%= TRType & TRClass %>';" onKeyDown="testValidity(this, '<%= asc(negativeScaleMax) %>', '<%= useNA %>', '<%= useNegativeScale %>', '<% if i = maxQuestion then response.write "sc_scores_" & i else response.write "sc_scores_" & (i + 1) end if %>');" name="sc_scores_<%= i %>" id="sc_scores_<%= i %>" maxlength="2" size="2" value="<%= negativeScaleNum %>" tabIndex="<%= i + 5 %>" /></td>
    I modify it so I can enter the "-" but when I enter number it will just remove the - sign.

    How can I achieve so I can add negative number. Thanks

  2. #2
    Join Date
    Aug 2008
    Location
    Sweden
    Posts
    227
    When useNegativeScale is set and you check if the key pressed is a number you currently set box.value to that number. You should just simply prepend "-" when setting the value there.

    box.value = "-" + (event.keyCode - 96);

  3. #3
    Join Date
    Jan 2013
    Posts
    10
    I tried your suggestion and input "-"... it automatically show -13.. which is wrong..

    I want to input "-" then input number. Please advise...

  4. #4
    Join Date
    Aug 2008
    Location
    Sweden
    Posts
    227
    Only include the hyphen if the user has entered a hyphen before then...

  5. #5
    Join Date
    Jan 2013
    Posts
    10
    what do you mean? I just want to input hyphen or subtract or dash sign, and then number inorder for me to have a negative number..

  6. #6
    Join Date
    Jan 2013
    Posts
    10
    Anyone wants to help me please. I just want to input a negative number based from the current code above.

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
HTML5 Development Center



Recent Articles