selvalexample.htm

来自「The goal of this library is to make ODBC」· HTM 代码 · 共 44 行

<pre><code><span class="codeComment">// Assign valid defaults for null values</span>

class Example
{
  public:					<span class="codeComment">// tablename.columnname:</span>
	int exampleInt;	    			<span class="codeComment">// DB_EXAMPLE.INT_VALUE</span>
	string exampleStr;			<span class="codeComment">// DB_EXAMPLE.STRING_VALUE</span>
	double exampleDouble;			<span class="codeComment">// DB_EXAMPLE.DOUBLE_VALUE</span>
	long exampleLong;			<span class="codeComment">// DB_EXAMPLE.EXAMPLE_LONG</span>
	TIMESTAMP_STRUCT exampleDate;		<span class="codeComment">// DB_EXAMPLE.EXAMPLE_DATE</span>
};

<span class="codeComment">// Validation behavior, assign default values for NULL fields</span>
template&lt;&gt; class dtl::DefaultSelValidate&lt;Example&gt; 
{
public:
bool operator()(BoundIOs &amp;boundIOs, Example &amp;rowbuf) {
	if (boundIOs[&quot;INT_VALUE&quot;].IsNull()) {
		rowbuf.exampleInt = 0;	
	}
	if (boundIOs[&quot;STRING_VALUE&quot;].IsNull()) {
		rowbuf.exampleStr = &quot;&quot;;	
	}
	if (boundIOs[&quot;DOUBLE_VALUE&quot;].IsNull()) {
		rowbuf.exampleDouble = 0;	
	}
	if (boundIOs[&quot;EXAMPLE_LONG&quot;].IsNull()) {
		rowbuf.exampleLong = 0;	
	}
	if (boundIOs[&quot;EXAMPLE_DATE&quot;].IsNull()) {
		const TIMESTAMP_STRUCT defaultDate = {2000, 1, 1, 0, 0, 0, 0};
		rowbuf.exampleDate = defaultDate;	
	}

	<span class="codeComment">// Now check that values are in acceptable range
	// Return false/failure if values out of range</span>
	if (rowbuf.exampleDouble &gt; 100)
		return false;

	return true;	// data is OK
}

};</code></pre>