How to set a column value based on another column value

Question

I have a sharepoint list which contains a drop down of the values , Immediate , Hire , Specific

I have another column Grace Period which is a numeric

When the drop down column Immediate is selected the Grace Period should be a fixed zero

When the drop down Hire is selected the user can add Grace Period, but it should not be zero

When the drop down is Specific the user can add either zero or any number

How can this be achieved.

Can column validation be used. I am confused about the formula that can be used

Any help is highly appreciated

Answer 1

You can do it with a bit of JavaScript.. But that is messy and its not good to include JavaScript in default List Forms..

Since you have SharePoint Enterprise, I will suggest you to edit the List Forms in InfoPath and using Rules set the value of Grace Period on value change of drop down.

Automatically Set Field Value in InfoPath

UPDATE

Since you have Standard Version, InfoPath forms will not be available.. You can try doing it from JavaScript

// Use drop down field title below
$("input[title='title_of_the_field']").change(function() {
   setGracePeriod(this.value);
});

function setGracePeriod(dropdownValue)
{
  switch(dropdownValue)
  {
      case "Immediate":
      //Here you should use Grace Period field title
      $("input[title='title_of_the_field']").val('0');
      break;
  }
}

PS: You should reference JQuery Library in Master Page

Reference

How do I get the value of a SharePoint:FormField with javascript?