Here are six essential string functions to extend the functions for strings in javascript. If you are already using a major javascript framework like MooTools or Prototype, you may find many of these redundant with your javascript framework. In our case, we used YUI to develop our Trendics Control Panel and YUI didn’t include these type of string prototype functions (similar functions are available in YAHOO.lang but these are not as convenient to call)…

// Returns the string with all the beginning
// and ending whitespace removed
String.prototype.trim = function() {
  return this.replace(/^\s+/, '').replace(/\s+$/, '');
};

// Returns the left x characters of the string
String.prototype.left = function(count) {
  if (this.length>count) {
    return this.substring(0, count);
  }
  else {
    return this;
  }
}

// Returns the right x characters of the string
String.prototype.right = function(count) {
  if (this.length>count) {
    return this.substring(this.length-count, this.length);
  }
  else {
    return this;
  }
}

// Returns true if the string begins with value
String.prototype.startsWith = function(value) {
  if (this.length<value.length) {
    return false;
  }
  else {
    return this.substring(0, value.length)===value;
  }
}

// Returns true if the string ends with value
String.prototype.endsWith = function(value) {
   if (this.length<value.length) {
    return false;
  }
  else {
    return this.substring(this.length-value.length, this.length)===value;
  }
}

// Returns a shortened version of the string
// suffixed with "..." if characters are truncated
// from the original string
String.prototype.shorten = function(maxLength) {
  if (!this) {
    result = null;
  }
  else if (this.length>maxLength) {
    preferredSize = maxLength-'...'.length;
    if (preferredSize>0) {
      result = this.left(preferredSize) + '...';
    }
    else {
      result = this.left(maxLength);
    }
  }
  else {
    result = this;
  }
  return result;
}

The functions above can be invoked on any javascript string like this…

alert(" Hello ".trim());

var message = "This is a longer sentence.";
alert(message.shorten(10));

Hope this helps.

We’ve launched status badges that allow you to display the status of any alert rule on your own website. So, you might create this display on your own website…

Server	HTTP	POP3	FTP
Jupiter
Saturn
Venus

To embed the alert rule statuses in your pages, you can get the Status Badge HTML simply by…

1. Logging in at https://cp.trendics.com
2. Clicking Devices in the top navigation bar
3. Clicking on Manage Status Badge
4. Copying the displayed Badge HTML

You can also customize the images used for the status on the same Manage Status Badge form. Enjoy!

I recently spent 3 hours pulling my hair out trying to fix a MySQL stored procedure that wasn’t working as expected. I’ve boiled the ultimate problem down to a simple example below. Can you spot the problem?

# First, let's create some sample data
CREATE TABLE TrendicsTest (
DateTime DATETIME NOT NULL,
Value INT NOT NULL,
UNIQUE KEY DateTime (DateTime)
);
INSERT INTO TrendicsTest VALUES ('2008-01-01 01:00', 1);
INSERT INTO TrendicsTest VALUES ('2008-01-01 02:00', 2);