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Another way to prepare the workstep is to use signature field placeholder (‘sig’) or advanced tags in the document. For signature field placeholders you need to get the AdHocWorkstepConfiguration via API (GetAdHocWorkstepConfiguration_v1) and for advanced tags you have first to perform a prepare call (PrepareSendEnvelopeSteps_v1). An alternative is to use the Workstep Designer. The workstep designer can help you creating a workstep xml and you can directly try it in the SignAnyWhere Viewer (the eSignAnyWhere default signing client).
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Input Validation for Form Fields 
In the workstep configuration you can define a form field valdiation for text fields.
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