# C1.C1Preview.DataBinding.DataSetField.Expression

## Content

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<h1 id="C1_C1Preview_DataBinding_DataSetField_Expression_" data-uid="C1.C1Preview.DataBinding.DataSetField.Expression*">Expression Property
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<div class="markdown level0 conceptual"></div>



<a id="C1_C1Preview_DataBinding_DataSetField_Expression_" data-uid="C1.C1Preview.DataBinding.DataSetField.Expression*"></a>
<h4 id="C1_C1Preview_DataBinding_DataSetField_Expression" data-uid="C1.C1Preview.DataBinding.DataSetField.Expression">Expression</h4>
<div class="markdown level1 summary"><p>Gets the <a class="xref" href="C1.C1Preview.DataBinding.Expression.html">Expression</a> used
to calculate the value of the current field.</p>
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If this expression is not empty, the field is
a <b>calculated field</b> (as opposed to a <b>data field</b>).
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<h5 class="declaration">Declaration</h5>
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  <pre><code class="lang-csharp hljs">public Expression Expression { get; }</code></pre>
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  <pre><code class="lang-vbnet hljs">Public ReadOnly Property Expression As Expression</code></pre>
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<h5 id="C1_C1Preview_DataBinding_DataSetField_Expression_remarks">Remarks</h5>
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This property is never <b>null</b> (<b>Nothing</b> in VB), it always
returns an <a class="xref" href="C1.C1Preview.DataBinding.Expression.html">Expression</a> object,
which has empty <a class="xref" href="C1.C1Preview.DataBinding.Expression.Text.html#C1_C1Preview_DataBinding_Expression_Text">Text</a>
by default. (A non-empty <b>Text</b> string indicates a calculated field.)
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To specify an expression, set its <a class="xref" href="C1.C1Preview.DataBinding.Expression.Text.html#C1_C1Preview_DataBinding_Expression_Text">Text</a>
property, or the <a class="xref" href="C1.C1Preview.DataBinding.DataSetField.ExpressionText.html#C1_C1Preview_DataBinding_DataSetField_ExpressionText">ExpressionText</a> property on the
current field.
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Either this property or <a class="xref" href="C1.C1Preview.DataBinding.DataSetField.DataField.html#C1_C1Preview_DataBinding_DataSetField_DataField">DataField</a>, but not both,
should be defined on a <a class="xref" href="C1.C1Preview.DataBinding.DataSetField.html">DataSetField</a>. In case both
properties are defined, <a class="xref" href="C1.C1Preview.DataBinding.DataSetField.DataField.html#C1_C1Preview_DataBinding_DataSetField_DataField">DataField</a> is used, and
<b>Expression</b> is ignored.
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