How to change this default behavior? Let's say, display the date from a page's column (field) named "Published Date". You can do it without any coding! Following are the configuration steps to achieve this:
1. Verify the property internal name. You can go the library setting page, click the "Published Date" column, search the "Field" query string inside the URL, and that's column's internal name. It's "Publish%5x0020%5On":
2. Make that "PublishDate" property enable for search result web part to display:
2.1. Open SharePoint Centra Admin -> Manage Application -> Manage Service Application -> Search Application
2.2. Click "Metadate Properties" under "Queries and Results" category on the left panel
2.3. Click "New Managed Property" on the tool bar
2.4. Type "PublishDate" as property name, add "ows_Published_x0020_On" to the mapping, check "Allow this property to be used in scopes" and "Add managed property to custom results set retrieved on each query"
3. Re-crawl the whole content: click "Content Sources" under Crawling category, select the target content source and click "Start Full Crawl". Wait for crawling to be completed.
4. Update Search Core Result WebPart on search result page to display the newly added search property. Because not all content has such column (field), we need to conditionally display this field if it exists, otherwise show the original last modified date.
4.1. Edit the "Search Core Resul" WebPart on the search page, under "Display Properties" category, uncheck "Use Location Visualization".
4.2. Copy the value of "Fetched Proerpties" and paste it to a notepad, add <column name="PublishDate"> in front of <column name="Write"> then paste back the whole string (one line) as "Fetched Proerpties" value, something like:
<root xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"><Columns><Column Name="WorkId"/>...4.3. Click "XML Editor", search for:
<Column Name="PublishDate"/><Column Name="Write"/>...
<xsl:call-template name="DisplayString">Replaced by:
<xsl:with-param name="str" select="write"></xsl:with-param>
</xsl:call-template>
<xsl:choose>Now the "Published Date" is shown for those pages with this field defined, and last modified date displays for those pages without this field.
<xsl:when test="string-length(publishdate) > 0">
<xsl:call-template name="DisplayString">
<xsl:with-param name="str" select="publishdate"></xsl:with-param>
</xsl:call-template>
<xsl:otherwise>
<xsl:call-template name="DisplayString">
<xsl:with-param name="str" select="write"></xsl:with-param>
</xsl:call-template>
</xsl:otherwise>
</xsl:when></xsl:choose>
Note that "publishdate" in the XSLT condition is all lower case. I defined it as "PublishDate" in Search property, and I assumed it remains the same in search return. But that's not the case. Search application always returns a xml with all lower case property name. This can be verified by showing the original search result. In order to see the oringal search result, simply use the following xml for the Search Core Result WebPart:
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">The screen-shot of the original search return:
<xsl:output method="xml" version="1.0" encoding="UTF-8" indent="yes"/>
<xsl:template match="/">
<xmp><xsl:copy-of select="*"/></xmp>
</xsl:template>
</xsl:stylesheet>
