计算两个DateTimeOffsets之间的间距

				
					{"blocks":"<xml xmlns=\"https://developers.google.com/blockly/xml\"><block type=\"pxt-on-start\"><statement name=\"HANDLER\"><block type=\"variables_set\"><field name=\"VAR\">mainLayout</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"ScreenItem_createLayout\"/></value><next><block type=\"variables_set\"><field name=\"VAR\">mainScreen</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"Screen_create\"><value name=\"label\"><shadow type=\"text\"><field name=\"TEXT\">Main</field></shadow></value><value name=\"layout\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value></block></value><next><block type=\"variables_set\"><field name=\"VAR\">dateTimeOffset</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"DateTime_createDateTimeOffset\"><mutation xmlns=\"http://www.w3.org/1999/xhtml\" _expanded=\"5\" _input_init=\"true\"></mutation><value name=\"year\"><shadow type=\"math_number\"><field name=\"NUM\">2020</field></shadow></value><value name=\"month\"><shadow type=\"math_number\"><field name=\"NUM\">3</field></shadow></value><value name=\"day\"><shadow type=\"math_number\"><field name=\"NUM\">23</field></shadow></value><value name=\"hour\"><shadow type=\"math_number\"><field name=\"NUM\">5</field></shadow></value><value name=\"minute\"><shadow type=\"math_number\"><field name=\"NUM\">30</field></shadow></value><value name=\"second\"><shadow type=\"math_number\"><field name=\"NUM\">25</field></shadow></value></block></value><next><block type=\"variables_set\"><field name=\"VAR\">currentTime</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"DateTime_now\"/></value><next><block type=\"variables_set\"><field name=\"VAR\">duration</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"DateTime_DateTimeOffset_diff\"><field name=\"maxDurationUnit\">DurationUnit.Years</field><value name=\"dateTimeOffset\"><block type=\"variables_get\"><field name=\"VAR\">currentTime</field></block></value><value name=\"other\"><block type=\"variables_get\"><field name=\"VAR\">dateTimeOffset</field></block></value></block></value><next><block type=\"ScreenItem_Layout_add\"><value name=\"this\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value><value name=\"item\"><block type=\"Control_createTextBlock\"><mutation xmlns=\"http://www.w3.org/1999/xhtml\" _expanded=\"1\" _input_init=\"true\"></mutation><value name=\"text\"><block type=\"DateTime_Duration_toString\"><value name=\"duration\"><block type=\"variables_get\"><field name=\"VAR\">duration</field></block></value></block></value></block></value></block></next></block></next></block></next></block></next></block></next></block></statement></block></xml>"}