Variable 'X' is used before it has been assigned a value. A null reference exception could result at...
在自己做機房收費系統的過程中出現了這樣的一個現象:如圖 str1 下面出現了一行波浪線.同時提醒自己錯出現的錯誤.提示如下: Variable 'str1' is used before it has been assigned a value. A null reference exception could result at runtime. 在Build的時候會出現以下的警告: 如圖: 問
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相關文章
- 1. What are the differences between a pointer variable and a reference variable in C++?
- 2. 2021-01-26nested exception is java.lang.IllegalArgumentException: A null value cannot be assigned to
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- 6. Bitmap.getWidth() on a null object reference at webview.getDefaultVideoPoster
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- 8. org.hibernate.PropertyAccessException: Null value was assigned to a property of primitive type sette
- 9. efined in null, could not be registered. A bean with that name has already been defined in null and
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