总是显示找不到文件，说明这种参数获取方式不对
"${TestCaseFilePath}"\mcoupon-go.lemall.com.csv、${TestCaseFilePath}\mcoupon-go.lemall.com.csv，这两种方式都不行
显示：

2017/09/18 11:48:08 INFO  - jmeter.services.FileServer: Stored: "${TestCaseFilePath}"\mcoupon-go.lemall.com.csv Alias: "${TestCaseFilePath}"\mcoupon-go.lemall.com.csv@950204696 
2017/09/18 11:48:08 ERROR - jmeter.threads.JMeterThread: Test failed! java.lang.IllegalArgumentException: File mcoupon-go.lemall.com.csv must exist and be readable
    at org.apache.jmeter.services.FileServer.createBufferedReader(FileServer.java:421)
    at org.apache.jmeter.services.FileServer.getReader(FileServer.java:387)
    at org.apache.jmeter.services.FileServer.getParsedLine(FileServer.java:378)
    at org.apache.jmeter.config.CSVDataSet.iterationStart(CSVDataSet.java:197)
    at org.apache.jmeter.control.GenericController.fireIterationStart(GenericController.java:405)
    at org.apache.jmeter.control.GenericController.fireIterEvents(GenericController.java:397)
    at org.apache.jmeter.control.GenericController.next(GenericController.java:158)
    at org.apache.jmeter.control.LoopController.next(LoopController.java:123)
    at org.apache.jmeter.threads.AbstractThreadGroup.next(AbstractThreadGroup.java:87)
    at org.apache.jmeter.threads.JMeterThread.run(JMeterThread.java:247)
    at java.lang.Thread.run(Unknown Source)