Report Parameter Properties Dialog Box, General
Select General on the Report Parameters dialog box to change parameter value options such as the parameter name and the type of data represented by the parameter. In addition, you can allow parameters to return blank, null, or many values.
Options
Name
Type a case-sensitive name for the parameter. The name must begin with a letter and have letters, numbers, an underscore (_), and no spaces. For automatically-generated parameters, the name matches the query parameter in the dataset query. By default, manually-created parameters use names similar to ReportParameter1.Data type
Select the data type of the parameter. The data type of the parameter affects how a parameter can be used in an expression. The parameter data type must match the data type of the field in the dataset.Data type determines how a user enters parameter values on the report viewer toolbar, as described in the following list:
Boolean. The user selects True or False from a radio button.
DateTime. The user selects a date from a calendar control.
Integer. The user types values in a text box.
Float. The user types values in a text box.
Text. The user types values in a text box.
When available values are defined for a parameter, the user chooses values from a drop-down list, even when the data type is DateTime.
Allow blank value
Select this option if the value of the parameter can be an empty string.Allow null value
Select this option if the value of the parameter can be null.Allow multiple values
Select this option if the value for the parameter can be multiple values that are displayed in a drop-down list. Null values are not allowed. When this option is selected, check boxes are added to the list of available values in a parameter drop-down list. The top of the list includes a check box for Select All. Users can check the values that they want.