我有一个要求，我必须阅读CSV文件并在Jasper中准备一份报告。我可以在常规文本字段中使用CSV数据源。但是当我向Detail或Summary部分添加一个表时，它需要创建一个新的数据集。我成功创建了它，但是当报告运行时，它无法从CSV数据源获取数据，我收到一个空白报告。如果我使用数据库而不是CSV，同样的事情也有效。 Jasper有没有错误。
答案 0 :(得分：0)
对于表组件，您必须创建新数据源，您必须执行以下操作：拖动表组件并单击“新建数据集”，然后从连接/数据源下拉列表中选择CSV数据集。
答案 1 :(得分：0)
我遇到了同样的问题。要解决此问题，请转到表组件，右键单击，然后选择＆＃34;编辑数据源＆＃34;，选择＆＃34;连接数据源表达式＆＃34;并写：
((net.sf.jasperreports.engine.data.JRCsvDataSource)$P{REPORT_DATA_SOURCE})
答案 2 :(得分：0)
下面是一个示例JRXML，它显示了如何在表组件中使用CSV数据源。
请注意，您需要在子数据集中命名字段＆＃34; COLUMN _＆＃34; +列索引。这样在JRCsvDataSource＃getFieldValue中，您的字段将被正确定位，而无需在CSV文件中为列标题添加行。
<?xml version="1.0" encoding="UTF-8"?>
<!-- Created with Jaspersoft Studio version 6.3.0.final using JasperReports Library version 6.3.0 -->
<!-- 2016-08-23T13:06:06 -->
<jasperReport xmlns="http://jasperreports.sourceforge.net/jasperreports" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://jasperreports.sourceforge.net/jasperreports http://jasperreports.sourceforge.net/xsd/jasperreport.xsd" name="SimpleReportWithTable" pageWidth="595" pageHeight="842" whenNoDataType="AllSectionsNoDetail" columnWidth="555" leftMargin="20" rightMargin="20" topMargin="20" bottomMargin="20" uuid="b32b572d-c517-48ba-a44e-3402966e9932">
<property name="com.jaspersoft.studio.data.defaultdataadapter" value="SimpleCsvDataAdapter"/>
<style name="Table_TH" mode="Opaque" backcolor="#F0F8FF">
<box>
<pen lineWidth="0.5" lineColor="#000000"/>
<topPen lineWidth="0.5" lineColor="#000000"/>
<leftPen lineWidth="0.5" lineColor="#000000"/>
<bottomPen lineWidth="0.5" lineColor="#000000"/>
<rightPen lineWidth="0.5" lineColor="#000000"/>
</box>
</style>
<style name="Table_CH" mode="Opaque" backcolor="#BFE1FF">
<box>
<pen lineWidth="0.5" lineColor="#000000"/>
<topPen lineWidth="0.5" lineColor="#000000"/>
<leftPen lineWidth="0.5" lineColor="#000000"/>
<bottomPen lineWidth="0.5" lineColor="#000000"/>
<rightPen lineWidth="0.5" lineColor="#000000"/>
</box>
</style>
<style name="Table_TD" mode="Opaque" backcolor="#FFFFFF">
<box>
<pen lineWidth="0.5" lineColor="#000000"/>
<topPen lineWidth="0.5" lineColor="#000000"/>
<leftPen lineWidth="0.5" lineColor="#000000"/>
<bottomPen lineWidth="0.5" lineColor="#000000"/>
<rightPen lineWidth="0.5" lineColor="#000000"/>
</box>
<conditionalStyle>
<conditionExpression><![CDATA[new Boolean($V{REPORT_COUNT}.intValue()%2==0)]]></conditionExpression>
<style backcolor="#FBFDFF"/>
</conditionalStyle>
</style>
<subDataset name="Dataset1" uuid="76efa803-c263-4538-a39a-8ddb1712e58a">
<field name="COLUMN_0" class="java.lang.String"/>
<field name="COLUMN_1" class="java.lang.String"/>
<field name="COLUMN_2" class="java.lang.String"/>
<field name="COLUMN_3" class="java.lang.String"/>
<field name="COLUMN_4" class="java.lang.String"/>
<field name="COLUMN_5" class="java.lang.String"/>
<field name="COLUMN_6" class="java.lang.String"/>
<field name="COLUMN_7" class="java.lang.String"/>
<field name="COLUMN_8" class="java.lang.String"/>
</subDataset>
<parameter name="CSV_DATA_SOURCE" class="net.sf.jasperreports.engine.data.JRCsvDataSource" isForPrompting="false">
<defaultValueExpression><![CDATA[new net.sf.jasperreports.engine.data.JRCsvDataSource("path_to_csv_file")]]></defaultValueExpression>
</parameter>
<summary>
<band height="70" splitType="Stretch">
<componentElement>
<reportElement x="0" y="10" width="200" height="60" uuid="a5c67e1f-1b96-4044-b4d2-ba9da8502bab">
<property name="com.jaspersoft.studio.layout" value="com.jaspersoft.studio.editor.layout.VerticalRowLayout"/>
<property name="com.jaspersoft.studio.table.style.table_header" value="Table_TH"/>
<property name="com.jaspersoft.studio.table.style.column_header" value="Table_CH"/>
<property name="com.jaspersoft.studio.table.style.detail" value="Table_TD"/>
<property name="net.sf.jasperreports.export.headertoolbar.table.name" value=""/>
</reportElement>
<jr:table xmlns:jr="http://jasperreports.sourceforge.net/jasperreports/components" xsi:schemaLocation="http://jasperreports.sourceforge.net/jasperreports/components http://jasperreports.sourceforge.net/xsd/components.xsd" whenNoDataType="AllSectionsNoDetail">
<datasetRun subDataset="Dataset1" uuid="7738bf3c-ecda-4864-9804-c6319de53296">
<dataSourceExpression><![CDATA[$P{CSV_DATA_SOURCE}]]></dataSourceExpression>
</datasetRun>
<jr:column width="66" uuid="5c06dacd-68b4-4972-87e9-45dcbf181cbd">
<jr:columnHeader style="Table_CH" height="30">
<staticText>
<reportElement x="0" y="0" width="66" height="30" uuid="3ecb3cf8-02f5-4783-b407-9d36a3b76a9e"/>
<text><![CDATA[Row 1]]></text>
</staticText>
</jr:columnHeader>
<jr:detailCell style="Table_TD" height="30">
<textField>
<reportElement x="0" y="0" width="66" height="30" uuid="21db9e1b-c129-40f6-afd5-c8fc9b939112"/>
<textFieldExpression><![CDATA[$F{COLUMN_0}]]></textFieldExpression>
</textField>
</jr:detailCell>
</jr:column>
<jr:column width="66" uuid="45989e75-9ad1-4a48-ae63-ddaf380930e7">
<jr:columnHeader style="Table_CH" height="30">
<staticText>
<reportElement x="0" y="0" width="66" height="30" uuid="392ead1f-fd67-431c-8da6-3cf3dad9728d"/>
<text><![CDATA[Row 2]]></text>
</staticText>
</jr:columnHeader>
<jr:detailCell style="Table_TD" height="30">
<textField>
<reportElement x="0" y="0" width="66" height="30" uuid="1a1fb7ba-cec2-44f7-bdc7-3a3887302fb0"/>
<textFieldExpression><![CDATA[$F{COLUMN_1}]]></textFieldExpression>
</textField>
</jr:detailCell>
</jr:column>
<jr:column width="66" uuid="128a9867-c221-4862-a9ac-f5cc99e394f1">
<jr:columnHeader style="Table_CH" height="30">
<staticText>
<reportElement x="0" y="0" width="66" height="30" uuid="033b57f1-b3dd-4909-8ed7-84c99f92eccd"/>
<text><![CDATA[Row 3]]></text>
</staticText>
</jr:columnHeader>
<jr:detailCell style="Table_TD" height="30">
<textField>
<reportElement x="0" y="0" width="66" height="30" uuid="0d2027c4-e761-4e14-b093-31be3c0493e0"/>
<textFieldExpression><![CDATA[$F{COLUMN_2}]]></textFieldExpression>
</textField>
</jr:detailCell>
</jr:column>
</jr:table>
</componentElement>
</band>
</summary>
</jasperReport>