56 lines
1.5 KiB
Markdown
56 lines
1.5 KiB
Markdown
# GlobalVariableCheck
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Checks the existence of a global variable with the specified name
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```
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bool GlobalVariableCheck(
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string name // Global variable name
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);
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```
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Parameters
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name
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[in] Global variable name.
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Return Value
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Returns true, if the global variable exists, otherwise returns false.
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Global variables exist in the client terminal during 4 weeks since their last use, then they are automatically deleted.
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Example:
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```
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#property copyright "Copyright 2025, MetaQuotes Ltd."
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#property link "https://www.mql5.com"
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#property version "1.00"
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#define GV_NAME "TestGlobalVariableCheck"
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//+------------------------------------------------------------------+
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//| Script program start function |
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//+------------------------------------------------------------------+
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void OnStart()
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{
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//--- get the flag of the client terminal global variable named GV_NAME
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bool exist=GlobalVariableCheck(GV_NAME);
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PrintFormat("Terminal global variable named \"%s\" %s", GV_NAME, (exist ? "exists" : "does not exist"));
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/*
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result in the presence of a global variable:
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Terminal global variable named "TestGlobalVariableCheck" exists
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result in the absence of a global variable:
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Terminal global variable named "TestGlobalVariableCheck" does not exist
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*/
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}
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```
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See also
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[GlobalVariableTime()](/en/docs/globals/globalvariabletime)
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