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檢查JsonValue是否在正確的類型

JsonValue是

				
					{"blocks":"<xml xmlns=\"https://developers.google.com/blockly/xml\"><block type=\"Json_JsonValue_is\"><field name=\"type\">JsonValueDataType.String</field><value name=\"jsonValue\"><block type=\"variables_get\"><field name=\"VAR\">jsonValue</field></block></value></block></xml>"}
				
			

這積木是用作檢查JsonValue是否在正確的類型。

參數:

          • Json Value

          • 情況:字串(預設)/數字/布林值/陣列/物件/null

輸出:布林值(True/False)

示例代碼:

使用一個if-else條件式來檢查它是不是字串。

				
					{"blocks":"<xml xmlns=\"https://developers.google.com/blockly/xml\"><block type=\"controls_if\"><mutation else=\"1\"/><value name=\"IF0\"><shadow type=\"logic_boolean\"><field name=\"BOOL\">TRUE</field></shadow><block type=\"Json_JsonValue_is\"><field name=\"type\">JsonValueDataType.String</field><value name=\"jsonValue\"><block type=\"variables_get\"><field name=\"VAR\">isString</field></block></value></block></value><statement name=\"DO0\"><block type=\"Control_TextBlock_setContent\"><value name=\"this\"><block type=\"variables_get\"><field name=\"VAR\">checkString</field></block></value><value name=\"content\"><shadow type=\"text\"><field name=\"TEXT\">This is a String.</field></shadow></value></block></statement><statement name=\"ELSE\"><block type=\"Control_TextBlock_setContent\"><value name=\"this\"><block type=\"variables_get\"><field name=\"VAR\">checkString</field></block></value><value name=\"content\"><shadow type=\"text\"><field name=\"TEXT\">This is not a String.</field></shadow></value></block></statement></block></xml>"}
				
			
				
					{"blocks":"<xml xmlns=\"https://developers.google.com/blockly/xml\"><variables><variable>mainLayout</variable><variable>mainScreen</variable><variable>isString</variable><variable>checkString</variable></variables><block type=\"pxt-on-start\" x=\"0\" y=\"0\"><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\">isString</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"Json_parse\"><value name=\"str\"><shadow type=\"text\"><field name=\"TEXT\">\"hello\"</field></shadow></value></block></value><next><block type=\"variables_set\"><field name=\"VAR\">checkString</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"Control_createTextBlock\"><mutation xmlns=\"http://www.w3.org/1999/xhtml\" _expanded=\"0\" _input_init=\"false\"></mutation></block></value><next><block type=\"controls_if\"><mutation else=\"1\"/><value name=\"IF0\"><shadow type=\"logic_boolean\"><field name=\"BOOL\">TRUE</field></shadow><block type=\"Json_JsonValue_is\"><field name=\"type\">JsonValueDataType.String</field><value name=\"jsonValue\"><block type=\"variables_get\"><field name=\"VAR\">isString</field></block></value></block></value><statement name=\"DO0\"><block type=\"Control_TextBlock_setContent\"><value name=\"this\"><block type=\"variables_get\"><field name=\"VAR\">checkString</field></block></value><value name=\"content\"><shadow type=\"text\"><field name=\"TEXT\">This is a String.</field></shadow></value></block></statement><statement name=\"ELSE\"><block type=\"Control_TextBlock_setContent\"><value name=\"this\"><block type=\"variables_get\"><field name=\"VAR\">checkString</field></block></value><value name=\"content\"><shadow type=\"text\"><field name=\"TEXT\">This is not a String.</field></shadow></value></block></statement><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=\"Json_JsonValue_stringify\"><mutation xmlns=\"http://www.w3.org/1999/xhtml\" _expanded=\"0\" _input_init=\"false\"></mutation><value name=\"jsonValue\"><block type=\"variables_get\"><field name=\"VAR\">isString</field></block></value></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=\"variables_get\"><field name=\"VAR\">checkString</field></block></value></block></next></block></next></block></next></block></next></block></next></block></next></block></statement></block></xml>"}
				
			

當檢查是否字串時,輸出結果:

當檢查是否數字時,輸出結果:

當檢查是否布林值時,輸出結果:

當檢查是否陣列時,輸出結果:

當檢查是否物件時,輸出結果:

當檢查是否null時,輸出結果: